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CREATE TABLE

   CREATE TABLE — define a new table

Synopsis

CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXI
STS ] table_name ( [
  { column_name data_type [ STORAGE { PLAIN | EXTERNAL | EXTENDED | MAIN | DEFAU
LT } ] [ COMPRESSION compression_method ] [ COLLATE collation ] [ column_constra
int [ ... ] ]
    | table_constraint
    | LIKE source_table [ like_option ... ] }
    [, ... ]
] )
[ INHERITS ( parent_table [, ... ] ) ]
[ PARTITION BY { RANGE | LIST | HASH } ( { column_name | ( expression ) } [ COLL
ATE collation ] [ opclass ] [, ... ] ) ]
[ USING method ]
[ WITH ( storage_parameter [= value] [, ... ] ) | WITHOUT OIDS ]
[ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]
[ TABLESPACE tablespace_name ]

CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXI
STS ] table_name
    OF type_name [ (
  { column_name [ WITH OPTIONS ] [ column_constraint [ ... ] ]
    | table_constraint }
    [, ... ]
) ]
[ PARTITION BY { RANGE | LIST | HASH } ( { column_name | ( expression ) } [ COLL
ATE collation ] [ opclass ] [, ... ] ) ]
[ USING method ]
[ WITH ( storage_parameter [= value] [, ... ] ) | WITHOUT OIDS ]
[ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]
[ TABLESPACE tablespace_name ]

CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXI
STS ] table_name
    PARTITION OF parent_table [ (
  { column_name [ WITH OPTIONS ] [ column_constraint [ ... ] ]
    | table_constraint }
    [, ... ]
) ] { FOR VALUES partition_bound_spec | DEFAULT }
[ PARTITION BY { RANGE | LIST | HASH } ( { column_name | ( expression ) } [ COLL
ATE collation ] [ opclass ] [, ... ] ) ]
[ USING method ]
[ WITH ( storage_parameter [= value] [, ... ] ) | WITHOUT OIDS ]
[ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]
[ TABLESPACE tablespace_name ]

where column_constraint is:

[ CONSTRAINT constraint_name ]
{ NOT NULL [ NO INHERIT ]  |
  NULL |
  CHECK ( expression ) [ NO INHERIT ] |
  DEFAULT default_expr |
  GENERATED ALWAYS AS ( generation_expr ) [ STORED | VIRTUAL ] |
  GENERATED { ALWAYS | BY DEFAULT } AS IDENTITY [ ( sequence_options ) ] |
  UNIQUE [ NULLS [ NOT ] DISTINCT ] index_parameters |
  PRIMARY KEY index_parameters |
  REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL | MATCH PARTIAL | MATCH SIM
PLE ]
    [ ON DELETE referential_action ] [ ON UPDATE referential_action ] }
[ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ] [ E
NFORCED | NOT ENFORCED ]

and table_constraint is:

[ CONSTRAINT constraint_name ]
{ CHECK ( expression ) [ NO INHERIT ] |
  NOT NULL column_name [ NO INHERIT ] |
  UNIQUE [ NULLS [ NOT ] DISTINCT ] ( column_name [, ... ] [, column_name WITHOU
T OVERLAPS ] ) index_parameters |
  PRIMARY KEY ( column_name [, ... ] [, column_name WITHOUT OVERLAPS ] ) index_p
arameters |
  EXCLUDE [ USING index_method ] ( exclude_element WITH operator [, ... ] ) inde
x_parameters [ WHERE ( predicate ) ] |
  FOREIGN KEY ( column_name [, ... ] [, PERIOD column_name ] ) REFERENCES reftab
le [ ( refcolumn [, ... ] [, PERIOD refcolumn ] ) ]
    [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ] [ ON DELETE referential_action
 ] [ ON UPDATE referential_action ] }
[ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ] [ E
NFORCED | NOT ENFORCED ]

and like_option is:

{ INCLUDING | EXCLUDING } { COMMENTS | COMPRESSION | CONSTRAINTS | DEFAULTS | GE
NERATED | IDENTITY | INDEXES | STATISTICS | STORAGE | ALL }

and partition_bound_spec is:

IN ( partition_bound_expr [, ...] ) |
FROM ( { partition_bound_expr | MINVALUE | MAXVALUE } [, ...] )
  TO ( { partition_bound_expr | MINVALUE | MAXVALUE } [, ...] ) |
WITH ( MODULUS numeric_literal, REMAINDER numeric_literal )

index_parameters in UNIQUE, PRIMARY KEY, and EXCLUDE constraints are:

[ INCLUDE ( column_name [, ... ] ) ]
[ WITH ( storage_parameter [= value] [, ... ] ) ]
[ USING INDEX TABLESPACE tablespace_name ]

exclude_element in an EXCLUDE constraint is:

{ column_name | ( expression ) } [ COLLATE collation ] [ opclass [ ( opclass_par
ameter = value [, ... ] ) ] ] [ ASC | DESC ] [ NULLS { FIRST | LAST } ]

referential_action in a FOREIGN KEY/REFERENCES constraint is:

{ NO ACTION | RESTRICT | CASCADE | SET NULL [ ( column_name [, ... ] ) ] | SET D
EFAULT [ ( column_name [, ... ] ) ] }

Description

   CREATE TABLE will create a new, initially empty table in the current
   database. The table will be owned by the user issuing the command.

   If a schema name is given (for example, CREATE TABLE myschema.mytable
   ...) then the table is created in the specified schema. Otherwise it is
   created in the current schema. Temporary tables exist in a special
   schema, so a schema name cannot be given when creating a temporary
   table. The name of the table must be distinct from the name of any
   other relation (table, sequence, index, view, materialized view, or
   foreign table) in the same schema.

   CREATE TABLE also automatically creates a data type that represents the
   composite type corresponding to one row of the table. Therefore, tables
   cannot have the same name as any existing data type in the same schema.

   The optional constraint clauses specify constraints (tests) that new or
   updated rows must satisfy for an insert or update operation to succeed.
   A constraint is an SQL object that helps define the set of valid values
   in the table in various ways.

   There are two ways to define constraints: table constraints and column
   constraints. A column constraint is defined as part of a column
   definition. A table constraint definition is not tied to a particular
   column, and it can encompass more than one column. Every column
   constraint can also be written as a table constraint; a column
   constraint is only a notational convenience for use when the constraint
   only affects one column.

   To be able to create a table, you must have USAGE privilege on all
   column types or the type in the OF clause, respectively.

Parameters

   TEMPORARY or TEMP #
          If specified, the table is created as a temporary table.
          Temporary tables are automatically dropped at the end of a
          session, or optionally at the end of the current transaction
          (see ON COMMIT below). The default search_path includes the
          temporary schema first and so identically named existing
          permanent tables are not chosen for new plans while the
          temporary table exists, unless they are referenced with
          schema-qualified names. Any indexes created on a temporary table
          are automatically temporary as well.

          The autovacuum daemon cannot access and therefore cannot vacuum
          or analyze temporary tables. For this reason, appropriate vacuum
          and analyze operations should be performed via session SQL
          commands. For example, if a temporary table is going to be used
          in complex queries, it is wise to run ANALYZE on the temporary
          table after it is populated.

          Optionally, GLOBAL or LOCAL can be written before TEMPORARY or
          TEMP. This presently makes no difference in PostgreSQL and is
          deprecated; see Compatibility below.

   UNLOGGED #
          If specified, the table is created as an unlogged table. Data
          written to unlogged tables is not written to the write-ahead log
          (see Chapter 28), which makes them considerably faster than
          ordinary tables. However, they are not crash-safe: an unlogged
          table is automatically truncated after a crash or unclean
          shutdown. The contents of an unlogged table are also not
          replicated to standby servers. Any indexes created on an
          unlogged table are automatically unlogged as well.

          If this is specified, any sequences created together with the
          unlogged table (for identity or serial columns) are also created
          as unlogged.

          This form is not supported for partitioned tables.

   IF NOT EXISTS #
          Do not throw an error if a relation with the same name already
          exists. A notice is issued in this case. Note that there is no
          guarantee that the existing relation is anything like the one
          that would have been created.

   table_name #
          The name (optionally schema-qualified) of the table to be
          created.

   OF type_name #
          Creates a typed table, which takes its structure from the
          specified stand-alone composite type (that is, one created using
          CREATE TYPE) though it still produces a new composite type as
          well. The table will have a dependency on the referenced type,
          meaning that cascaded alter and drop actions on that type will
          propagate to the table.

          A typed table always has the same column names and data types as
          the type it is derived from, so you cannot specify additional
          columns. But the CREATE TABLE command can add defaults and
          constraints to the table, as well as specify storage parameters.

   column_name #
          The name of a column to be created in the new table.

   data_type #
          The data type of the column. This can include array specifiers.
          For more information on the data types supported by PostgreSQL,
          refer to Chapter 8.

   COLLATE collation #
          The COLLATE clause assigns a collation to the column (which must
          be of a collatable data type). If not specified, the column data
          type's default collation is used.

   STORAGE { PLAIN | EXTERNAL | EXTENDED | MAIN | DEFAULT } #
          This form sets the storage mode for the column. This controls
          whether this column is held inline or in a secondary TOAST
          table, and whether the data should be compressed or not. PLAIN
          must be used for fixed-length values such as integer and is
          inline, uncompressed. MAIN is for inline, compressible data.
          EXTERNAL is for external, uncompressed data, and EXTENDED is for
          external, compressed data. Writing DEFAULT sets the storage mode
          to the default mode for the column's data type. EXTENDED is the
          default for most data types that support non-PLAIN storage. Use
          of EXTERNAL will make substring operations on very large text
          and bytea values run faster, at the penalty of increased storage
          space. See Section 66.2 for more information.

   COMPRESSION compression_method #
          The COMPRESSION clause sets the compression method for the
          column. Compression is supported only for variable-width data
          types, and is used only when the column's storage mode is main
          or extended. (See ALTER TABLE for information on column storage
          modes.) Setting this property for a partitioned table has no
          direct effect, because such tables have no storage of their own,
          but the configured value will be inherited by newly-created
          partitions. The supported compression methods are pglz and lz4.
          (lz4 is available only if --with-lz4 was used when building
          PostgreSQL.) In addition, compression_method can be default to
          explicitly specify the default behavior, which is to consult the
          default_toast_compression setting at the time of data insertion
          to determine the method to use.

   INHERITS ( parent_table [, ... ] ) #
          The optional INHERITS clause specifies a list of tables from
          which the new table automatically inherits all columns. Parent
          tables can be plain tables or foreign tables.

          Use of INHERITS creates a persistent relationship between the
          new child table and its parent table(s). Schema modifications to
          the parent(s) normally propagate to children as well, and by
          default the data of the child table is included in scans of the
          parent(s).

          If the same column name exists in more than one parent table, an
          error is reported unless the data types of the columns match in
          each of the parent tables. If there is no conflict, then the
          duplicate columns are merged to form a single column in the new
          table. If the column name list of the new table contains a
          column name that is also inherited, the data type must likewise
          match the inherited column(s), and the column definitions are
          merged into one. If the new table explicitly specifies a default
          value for the column, this default overrides any defaults from
          inherited declarations of the column. Otherwise, any parents
          that specify default values for the column must all specify the
          same default, or an error will be reported.

          CHECK constraints are merged in essentially the same way as
          columns: if multiple parent tables and/or the new table
          definition contain identically-named CHECK constraints, these
          constraints must all have the same check expression, or an error
          will be reported. Constraints having the same name and
          expression will be merged into one copy. A constraint marked NO
          INHERIT in a parent will not be considered. Notice that an
          unnamed CHECK constraint in the new table will never be merged,
          since a unique name will always be chosen for it.

          Column STORAGE settings are also copied from parent tables.

          If a column in the parent table is an identity column, that
          property is not inherited. A column in the child table can be
          declared identity column if desired.

   PARTITION BY { RANGE | LIST | HASH } ( { column_name | ( expression ) }
          [ opclass ] [, ...] ) #
          The optional PARTITION BY clause specifies a strategy of
          partitioning the table. The table thus created is called a
          partitioned table. The parenthesized list of columns or
          expressions forms the partition key for the table. When using
          range or hash partitioning, the partition key can include
          multiple columns or expressions (up to 32, but this limit can be
          altered when building PostgreSQL), but for list partitioning,
          the partition key must consist of a single column or expression.

          Range and list partitioning require a btree operator class,
          while hash partitioning requires a hash operator class. If no
          operator class is specified explicitly, the default operator
          class of the appropriate type will be used; if no default
          operator class exists, an error will be raised. When hash
          partitioning is used, the operator class used must implement
          support function 2 (see Section 36.16.3 for details).

          A partitioned table is divided into sub-tables (called
          partitions), which are created using separate CREATE TABLE
          commands. The partitioned table is itself empty. A data row
          inserted into the table is routed to a partition based on the
          value of columns or expressions in the partition key. If no
          existing partition matches the values in the new row, an error
          will be reported.

          See Section 5.12 for more discussion on table partitioning.

   PARTITION OF parent_table { FOR VALUES partition_bound_spec | DEFAULT }
          #
          Creates the table as a partition of the specified parent table.
          The table can be created either as a partition for specific
          values using FOR VALUES or as a default partition using DEFAULT.
          Any indexes, constraints and user-defined row-level triggers
          that exist in the parent table are cloned on the new partition.

          The partition_bound_spec must correspond to the partitioning
          method and partition key of the parent table, and must not
          overlap with any existing partition of that parent. The form
          with IN is used for list partitioning, the form with FROM and TO
          is used for range partitioning, and the form with WITH is used
          for hash partitioning.

          partition_bound_expr is any variable-free expression
          (subqueries, window functions, aggregate functions, and
          set-returning functions are not allowed). Its data type must
          match the data type of the corresponding partition key column.
          The expression is evaluated once at table creation time, so it
          can even contain volatile expressions such as CURRENT_TIMESTAMP.

          When creating a list partition, NULL can be specified to signify
          that the partition allows the partition key column to be null.
          However, there cannot be more than one such list partition for a
          given parent table. NULL cannot be specified for range
          partitions.

          When creating a range partition, the lower bound specified with
          FROM is an inclusive bound, whereas the upper bound specified
          with TO is an exclusive bound. That is, the values specified in
          the FROM list are valid values of the corresponding partition
          key columns for this partition, whereas those in the TO list are
          not. Note that this statement must be understood according to
          the rules of row-wise comparison (Section 9.25.5). For example,
          given PARTITION BY RANGE (x,y), a partition bound FROM (1, 2) TO
          (3, 4) allows x=1 with any y>=2, x=2 with any non-null y, and
          x=3 with any y<4.

          The special values MINVALUE and MAXVALUE may be used when
          creating a range partition to indicate that there is no lower or
          upper bound on the column's value. For example, a partition
          defined using FROM (MINVALUE) TO (10) allows any values less
          than 10, and a partition defined using FROM (10) TO (MAXVALUE)
          allows any values greater than or equal to 10.

          When creating a range partition involving more than one column,
          it can also make sense to use MAXVALUE as part of the lower
          bound, and MINVALUE as part of the upper bound. For example, a
          partition defined using FROM (0, MAXVALUE) TO (10, MAXVALUE)
          allows any rows where the first partition key column is greater
          than 0 and less than or equal to 10. Similarly, a partition
          defined using FROM ('a', MINVALUE) TO ('b', MINVALUE) allows any
          rows where the first partition key column starts with "a".

          Note that if MINVALUE or MAXVALUE is used for one column of a
          partitioning bound, the same value must be used for all
          subsequent columns. For example, (10, MINVALUE, 0) is not a
          valid bound; you should write (10, MINVALUE, MINVALUE).

          Also note that some element types, such as timestamp, have a
          notion of "infinity", which is just another value that can be
          stored. This is different from MINVALUE and MAXVALUE, which are
          not real values that can be stored, but rather they are ways of
          saying that the value is unbounded. MAXVALUE can be thought of
          as being greater than any other value, including "infinity" and
          MINVALUE as being less than any other value, including "minus
          infinity". Thus the range FROM ('infinity') TO (MAXVALUE) is not
          an empty range; it allows precisely one value to be stored —
          "infinity".

          If DEFAULT is specified, the table will be created as the
          default partition of the parent table. This option is not
          available for hash-partitioned tables. A partition key value not
          fitting into any other partition of the given parent will be
          routed to the default partition.

          When a table has an existing DEFAULT partition and a new
          partition is added to it, the default partition must be scanned
          to verify that it does not contain any rows which properly
          belong in the new partition. If the default partition contains a
          large number of rows, this may be slow. The scan will be skipped
          if the default partition is a foreign table or if it has a
          constraint which proves that it cannot contain rows which should
          be placed in the new partition.

          When creating a hash partition, a modulus and remainder must be
          specified. The modulus must be a positive integer, and the
          remainder must be a non-negative integer less than the modulus.
          Typically, when initially setting up a hash-partitioned table,
          you should choose a modulus equal to the number of partitions
          and assign every table the same modulus and a different
          remainder (see examples, below). However, it is not required
          that every partition have the same modulus, only that every
          modulus which occurs among the partitions of a hash-partitioned
          table is a factor of the next larger modulus. This allows the
          number of partitions to be increased incrementally without
          needing to move all the data at once. For example, suppose you
          have a hash-partitioned table with 8 partitions, each of which
          has modulus 8, but find it necessary to increase the number of
          partitions to 16. You can detach one of the modulus-8
          partitions, create two new modulus-16 partitions covering the
          same portion of the key space (one with a remainder equal to the
          remainder of the detached partition, and the other with a
          remainder equal to that value plus 8), and repopulate them with
          data. You can then repeat this -- perhaps at a later time -- for
          each modulus-8 partition until none remain. While this may still
          involve a large amount of data movement at each step, it is
          still better than having to create a whole new table and move
          all the data at once.

          A partition must have the same column names and types as the
          partitioned table to which it belongs. Modifications to the
          column names or types of a partitioned table will automatically
          propagate to all partitions. CHECK constraints will be inherited
          automatically by every partition, but an individual partition
          may specify additional CHECK constraints; additional constraints
          with the same name and condition as in the parent will be merged
          with the parent constraint. Defaults may be specified separately
          for each partition. But note that a partition's default value is
          not applied when inserting a tuple through a partitioned table.

          Rows inserted into a partitioned table will be automatically
          routed to the correct partition. If no suitable partition
          exists, an error will occur.

          Operations such as TRUNCATE which normally affect a table and
          all of its inheritance children will cascade to all partitions,
          but may also be performed on an individual partition.

          Note that creating a partition using PARTITION OF requires
          taking an ACCESS EXCLUSIVE lock on the parent partitioned table.
          Likewise, dropping a partition with DROP TABLE requires taking
          an ACCESS EXCLUSIVE lock on the parent table. It is possible to
          use ALTER TABLE ATTACH/DETACH PARTITION to perform these
          operations with a weaker lock, thus reducing interference with
          concurrent operations on the partitioned table.

   LIKE source_table [ like_option ... ] #
          The LIKE clause specifies a table from which the new table
          automatically copies all column names, their data types, and
          their not-null constraints.

          Unlike INHERITS, the new table and original table are completely
          decoupled after creation is complete. Changes to the original
          table will not be applied to the new table, and it is not
          possible to include data of the new table in scans of the
          original table.

          Also unlike INHERITS, columns and constraints copied by LIKE are
          not merged with similarly named columns and constraints. If the
          same name is specified explicitly or in another LIKE clause, an
          error is signaled.

          The optional like_option clauses specify which additional
          properties of the original table to copy. Specifying INCLUDING
          copies the property, specifying EXCLUDING omits the property.
          EXCLUDING is the default. If multiple specifications are made
          for the same kind of object, the last one is used. The available
          options are:

        INCLUDING COMMENTS #
                Comments for the copied columns, constraints, and indexes
                will be copied. The default behavior is to exclude
                comments, resulting in the copied columns and constraints
                in the new table having no comments.

        INCLUDING COMPRESSION #
                Compression method of the columns will be copied. The
                default behavior is to exclude compression methods,
                resulting in columns having the default compression
                method.

        INCLUDING CONSTRAINTS #
                CHECK constraints will be copied. No distinction is made
                between column constraints and table constraints. Not-null
                constraints are always copied to the new table.

        INCLUDING DEFAULTS #
                Default expressions for the copied column definitions will
                be copied. Otherwise, default expressions are not copied,
                resulting in the copied columns in the new table having
                null defaults. Note that copying defaults that call
                database-modification functions, such as nextval, may
                create a functional linkage between the original and new
                tables.

        INCLUDING GENERATED #
                Any generation expressions as well as the stored/virtual
                choice of copied column definitions will be copied. By
                default, new columns will be regular base columns.

        INCLUDING IDENTITY #
                Any identity specifications of copied column definitions
                will be copied. A new sequence is created for each
                identity column of the new table, separate from the
                sequences associated with the old table.

        INCLUDING INDEXES #
                Indexes, PRIMARY KEY, UNIQUE, and EXCLUDE constraints on
                the original table will be created on the new table. Names
                for the new indexes and constraints are chosen according
                to the default rules, regardless of how the originals were
                named. (This behavior avoids possible duplicate-name
                failures for the new indexes.)

        INCLUDING STATISTICS #
                Extended statistics are copied to the new table.

        INCLUDING STORAGE #
                STORAGE settings for the copied column definitions will be
                copied. The default behavior is to exclude STORAGE
                settings, resulting in the copied columns in the new table
                having type-specific default settings. For more on STORAGE
                settings, see Section 66.2.

        INCLUDING ALL #
                INCLUDING ALL is an abbreviated form selecting all the
                available individual options. (It could be useful to write
                individual EXCLUDING clauses after INCLUDING ALL to select
                all but some specific options.)

          The LIKE clause can also be used to copy column definitions from
          views, foreign tables, or composite types. Inapplicable options
          (e.g., INCLUDING INDEXES from a view) are ignored.

   CONSTRAINT constraint_name #
          An optional name for a column or table constraint. If the
          constraint is violated, the constraint name is present in error
          messages, so constraint names like col must be positive can be
          used to communicate helpful constraint information to client
          applications. (Double-quotes are needed to specify constraint
          names that contain spaces.) If a constraint name is not
          specified, the system generates a name.

   NOT NULL [ NO INHERIT ] #
          The column is not allowed to contain null values.

          A constraint marked with NO INHERIT will not propagate to child
          tables.

   NULL #
          The column is allowed to contain null values. This is the
          default.

          This clause is only provided for compatibility with non-standard
          SQL databases. Its use is discouraged in new applications.

   CHECK ( expression ) [ NO INHERIT ] #
          The CHECK clause specifies an expression producing a Boolean
          result which new or updated rows must satisfy for an insert or
          update operation to succeed. Expressions evaluating to TRUE or
          UNKNOWN succeed. Should any row of an insert or update operation
          produce a FALSE result, an error exception is raised and the
          insert or update does not alter the database. A check constraint
          specified as a column constraint should reference that column's
          value only, while an expression appearing in a table constraint
          can reference multiple columns.

          Currently, CHECK expressions cannot contain subqueries nor refer
          to variables other than columns of the current row (see
          Section 5.5.1). The system column tableoid may be referenced,
          but not any other system column.

          A constraint marked with NO INHERIT will not propagate to child
          tables.

          When a table has multiple CHECK constraints, they will be tested
          for each row in alphabetical order by name, after checking NOT
          NULL constraints. (PostgreSQL versions before 9.5 did not honor
          any particular firing order for CHECK constraints.)

   DEFAULT default_expr #
          The DEFAULT clause assigns a default data value for the column
          whose column definition it appears within. The value is any
          variable-free expression (in particular, cross-references to
          other columns in the current table are not allowed). Subqueries
          are not allowed either. The data type of the default expression
          must match the data type of the column.

          The default expression will be used in any insert operation that
          does not specify a value for the column. If there is no default
          for a column, then the default is null.

   GENERATED ALWAYS AS ( generation_expr ) [ STORED | VIRTUAL ] #
          This clause creates the column as a generated column. The column
          cannot be written to, and when read the result of the specified
          expression will be returned.

          When VIRTUAL is specified, the column will be computed when it
          is read, and it will not occupy any storage. When STORED is
          specified, the column will be computed on write and will be
          stored on disk. VIRTUAL is the default.

          The generation expression can refer to other columns in the
          table, but not other generated columns. Any functions and
          operators used must be immutable. References to other tables are
          not allowed.

          A virtual generated column cannot have a user-defined type, and
          the generation expression of a virtual generated column must not
          reference user-defined functions or types, that is, it can only
          use built-in functions or types. This applies also indirectly,
          such as for functions or types that underlie operators or casts.
          (This restriction does not exist for stored generated columns.)

   GENERATED { ALWAYS | BY DEFAULT } AS IDENTITY [ ( sequence_options ) ]
          #
          This clause creates the column as an identity column. It will
          have an implicit sequence attached to it and in newly-inserted
          rows the column will automatically have values from the sequence
          assigned to it. Such a column is implicitly NOT NULL.

          The clauses ALWAYS and BY DEFAULT determine how explicitly
          user-specified values are handled in INSERT and UPDATE commands.

          In an INSERT command, if ALWAYS is selected, a user-specified
          value is only accepted if the INSERT statement specifies
          OVERRIDING SYSTEM VALUE. If BY DEFAULT is selected, then the
          user-specified value takes precedence. See INSERT for details.
          (In the COPY command, user-specified values are always used
          regardless of this setting.)

          In an UPDATE command, if ALWAYS is selected, any update of the
          column to any value other than DEFAULT will be rejected. If BY
          DEFAULT is selected, the column can be updated normally. (There
          is no OVERRIDING clause for the UPDATE command.)

          The optional sequence_options clause can be used to override the
          parameters of the sequence. The available options include those
          shown for CREATE SEQUENCE, plus SEQUENCE NAME name, LOGGED, and
          UNLOGGED, which allow selection of the name and persistence
          level of the sequence. Without SEQUENCE NAME, the system chooses
          an unused name for the sequence. Without LOGGED or UNLOGGED, the
          sequence will have the same persistence level as the table.

   UNIQUE [ NULLS [ NOT ] DISTINCT ] (column constraint)
          UNIQUE [ NULLS [ NOT ] DISTINCT ] ( column_name [, ... ] [,
          column_name WITHOUT OVERLAPS ] ) [ INCLUDE ( column_name [,
          ...]) ] (table constraint) #
          The UNIQUE constraint specifies that a group of one or more
          columns of a table can contain only unique values. The behavior
          of a unique table constraint is the same as that of a unique
          column constraint, with the additional capability to span
          multiple columns. The constraint therefore enforces that any two
          rows must differ in at least one of these columns.

          If the WITHOUT OVERLAPS option is specified for the last column,
          then that column is checked for overlaps instead of equality. In
          that case, the other columns of the constraint will allow
          duplicates so long as the duplicates don't overlap in the
          WITHOUT OVERLAPS column. (This is sometimes called a temporal
          key, if the column is a range of dates or timestamps, but
          PostgreSQL allows ranges over any base type.) In effect, such a
          constraint is enforced with an EXCLUDE constraint rather than a
          UNIQUE constraint. So for example UNIQUE (id, valid_at WITHOUT
          OVERLAPS) behaves like EXCLUDE USING GIST (id WITH =, valid_at
          WITH &&). The WITHOUT OVERLAPS column must have a range or
          multirange type. Empty ranges/multiranges are not permitted. The
          non-WITHOUT OVERLAPS columns of the constraint can be any type
          that can be compared for equality in a GiST index. By default,
          only range types are supported, but you can use other types by
          adding the btree_gist extension (which is the expected way to
          use this feature).

          For the purpose of a unique constraint, null values are not
          considered equal, unless NULLS NOT DISTINCT is specified.

          Each unique constraint should name a set of columns that is
          different from the set of columns named by any other unique or
          primary key constraint defined for the table. (Otherwise,
          redundant unique constraints will be discarded.)

          When establishing a unique constraint for a multi-level
          partition hierarchy, all the columns in the partition key of the
          target partitioned table, as well as those of all its descendant
          partitioned tables, must be included in the constraint
          definition.

          Adding a unique constraint will automatically create a unique
          btree index on the column or group of columns used in the
          constraint. But if the constraint includes a WITHOUT OVERLAPS
          clause, it will use a GiST index. The created index has the same
          name as the unique constraint.

          The optional INCLUDE clause adds to that index one or more
          columns that are simply “payload”: uniqueness is not enforced on
          them, and the index cannot be searched on the basis of those
          columns. However they can be retrieved by an index-only scan.
          Note that although the constraint is not enforced on included
          columns, it still depends on them. Consequently, some operations
          on such columns (e.g., DROP COLUMN) can cause cascaded
          constraint and index deletion.

   PRIMARY KEY (column constraint)
          PRIMARY KEY ( column_name [, ... ] [, column_name WITHOUT
          OVERLAPS ] ) [ INCLUDE ( column_name [, ...]) ] (table
          constraint) #
          The PRIMARY KEY constraint specifies that a column or columns of
          a table can contain only unique (non-duplicate), nonnull values.
          Only one primary key can be specified for a table, whether as a
          column constraint or a table constraint.

          The primary key constraint should name a set of columns that is
          different from the set of columns named by any unique constraint
          defined for the same table. (Otherwise, the unique constraint is
          redundant and will be discarded.)

          PRIMARY KEY enforces the same data constraints as a combination
          of UNIQUE and NOT NULL. However, identifying a set of columns as
          the primary key also provides metadata about the design of the
          schema, since a primary key implies that other tables can rely
          on this set of columns as a unique identifier for rows.

          When placed on a partitioned table, PRIMARY KEY constraints
          share the restrictions previously described for UNIQUE
          constraints.

          Adding a PRIMARY KEY constraint will automatically create a
          unique btree index on the column or group of columns used in the
          constraint, or GiST if WITHOUT OVERLAPS was specified.

          The optional INCLUDE clause adds to that index one or more
          columns that are simply “payload”: uniqueness is not enforced on
          them, and the index cannot be searched on the basis of those
          columns. However they can be retrieved by an index-only scan.
          Note that although the constraint is not enforced on included
          columns, it still depends on them. Consequently, some operations
          on such columns (e.g., DROP COLUMN) can cause cascaded
          constraint and index deletion.

   EXCLUDE [ USING index_method ] ( exclude_element WITH operator [, ... ]
          ) index_parameters [ WHERE ( predicate ) ] #
          The EXCLUDE clause defines an exclusion constraint, which
          guarantees that if any two rows are compared on the specified
          column(s) or expression(s) using the specified operator(s), not
          all of these comparisons will return TRUE. If all of the
          specified operators test for equality, this is equivalent to a
          UNIQUE constraint, although an ordinary unique constraint will
          be faster. However, exclusion constraints can specify
          constraints that are more general than simple equality. For
          example, you can specify a constraint that no two rows in the
          table contain overlapping circles (see Section 8.8) by using the
          && operator. The operator(s) are required to be commutative.

          Exclusion constraints are implemented using an index that has
          the same name as the constraint, so each specified operator must
          be associated with an appropriate operator class (see
          Section 11.10) for the index access method index_method. Each
          exclude_element defines a column of the index, so it can
          optionally specify a collation, an operator class, operator
          class parameters, and/or ordering options; these are described
          fully under CREATE INDEX.

          The access method must support amgettuple (see Chapter 63); at
          present this means GIN cannot be used. Although it's allowed,
          there is little point in using B-tree or hash indexes with an
          exclusion constraint, because this does nothing that an ordinary
          unique constraint doesn't do better. So in practice the access
          method will always be GiST or SP-GiST.

          The predicate allows you to specify an exclusion constraint on a
          subset of the table; internally this creates a partial index.
          Note that parentheses are required around the predicate.

          When establishing an exclusion constraint for a multi-level
          partition hierarchy, all the columns in the partition key of the
          target partitioned table, as well as those of all its descendant
          partitioned tables, must be included in the constraint
          definition. Additionally, those columns must be compared using
          the equality operator. These restrictions ensure that
          potentially-conflicting rows will exist in the same partition.
          The constraint may also refer to other columns which are not a
          part of any partition key, which can be compared using any
          appropriate operator.

   REFERENCES reftable [ ( refcolumn ) ] [ MATCH matchtype ] [ ON DELETE
          referential_action ] [ ON UPDATE referential_action ] (column
          constraint)
          FOREIGN KEY ( column_name [, ... ] [, PERIOD column_name ] )
          REFERENCES reftable [ ( refcolumn [, ... ] [, PERIOD refcolumn ]
          ) ] [ MATCH matchtype ] [ ON DELETE referential_action ] [ ON
          UPDATE referential_action ] (table constraint) #
          These clauses specify a foreign key constraint, which requires
          that a group of one or more columns of the new table must only
          contain values that match values in the referenced column(s) of
          some row of the referenced table. If the refcolumn list is
          omitted, the primary key of the reftable is used. Otherwise, the
          refcolumn list must refer to the columns of a non-deferrable
          unique or primary key constraint or be the columns of a
          non-partial unique index.

          If the last column is marked with PERIOD, it is treated in a
          special way. While the non-PERIOD columns are compared for
          equality (and there must be at least one of them), the PERIOD
          column is not. Instead, the constraint is considered satisfied
          if the referenced table has matching records (based on the
          non-PERIOD parts of the key) whose combined PERIOD values
          completely cover the referencing record's. In other words, the
          reference must have a referent for its entire duration. This
          column must be a range or multirange type. In addition, the
          referenced table must have a primary key or unique constraint
          declared with WITHOUT OVERLAPS. Finally, if the foreign key has
          a PERIOD column_name specification the corresponding refcolumn,
          if present, must also be marked PERIOD. If the refcolumn clause
          is omitted, and thus the reftable's primary key constraint
          chosen, the primary key must have its final column marked
          WITHOUT OVERLAPS.

          For each pair of referencing and referenced column, if they are
          of a collatable data type, then the collations must either be
          both deterministic or else both the same. This ensures that both
          columns have a consistent notion of equality.

          The user must have REFERENCES permission on the referenced table
          (either the whole table, or the specific referenced columns).
          The addition of a foreign key constraint requires a SHARE ROW
          EXCLUSIVE lock on the referenced table. Note that foreign key
          constraints cannot be defined between temporary tables and
          permanent tables.

          A value inserted into the referencing column(s) is matched
          against the values of the referenced table and referenced
          columns using the given match type. There are three match types:
          MATCH FULL, MATCH PARTIAL, and MATCH SIMPLE (which is the
          default). MATCH FULL will not allow one column of a multicolumn
          foreign key to be null unless all foreign key columns are null;
          if they are all null, the row is not required to have a match in
          the referenced table. MATCH SIMPLE allows any of the foreign key
          columns to be null; if any of them are null, the row is not
          required to have a match in the referenced table. MATCH PARTIAL
          is not yet implemented. (Of course, NOT NULL constraints can be
          applied to the referencing column(s) to prevent these cases from
          arising.)

          In addition, when the data in the referenced columns is changed,
          certain actions are performed on the data in this table's
          columns. The ON DELETE clause specifies the action to perform
          when a referenced row in the referenced table is being deleted.
          Likewise, the ON UPDATE clause specifies the action to perform
          when a referenced column in the referenced table is being
          updated to a new value. If the row is updated, but the
          referenced column is not actually changed, no action is done.
          Referential actions are executed as part of the data changing
          command, even if the constraint is deferred. There are the
          following possible actions for each clause:

        NO ACTION #
                Produce an error if the deletion or update would create a
                foreign key constraint violation. If the constraint is
                deferred, this error will be produced at constraint check
                time if there still exist any referencing rows. This is
                the default action.

        RESTRICT #
                Produce an error if a row to be deleted or updated matches
                a row in the referencing table. This prevents the action
                even if the state after the action would not violate the
                foreign key constraint. In particular, it prevents updates
                of referenced rows to values that are distinct but compare
                as equal. (But it does not prevent “no-op” updates that
                update a column to the same value.)

                In a temporal foreign key, this option is not supported.

        CASCADE #
                Delete any rows referencing the deleted row, or update the
                values of the referencing column(s) to the new values of
                the referenced columns, respectively.

                In a temporal foreign key, this option is not supported.

        SET NULL [ ( column_name [, ... ] ) ] #
                Set all of the referencing columns, or a specified subset
                of the referencing columns, to null. A subset of columns
                can only be specified for ON DELETE actions.

                In a temporal foreign key, this option is not supported.

        SET DEFAULT [ ( column_name [, ... ] ) ] #
                Set all of the referencing columns, or a specified subset
                of the referencing columns, to their default values. A
                subset of columns can only be specified for ON DELETE
                actions. (There must be a row in the referenced table
                matching the default values, if they are not null, or the
                operation will fail.)

                In a temporal foreign key, this option is not supported.

          If the referenced column(s) are changed frequently, it might be
          wise to add an index to the referencing column(s) so that
          referential actions associated with the foreign key constraint
          can be performed more efficiently.

   DEFERRABLE
          NOT DEFERRABLE #
          This controls whether the constraint can be deferred. A
          constraint that is not deferrable will be checked immediately
          after every command. Checking of constraints that are deferrable
          can be postponed until the end of the transaction (using the SET
          CONSTRAINTS command). NOT DEFERRABLE is the default. Currently,
          only UNIQUE, PRIMARY KEY, EXCLUDE, and REFERENCES (foreign key)
          constraints accept this clause. NOT NULL and CHECK constraints
          are not deferrable. Note that deferrable constraints cannot be
          used as conflict arbitrators in an INSERT statement that
          includes an ON CONFLICT DO UPDATE clause.

   INITIALLY IMMEDIATE
          INITIALLY DEFERRED #
          If a constraint is deferrable, this clause specifies the default
          time to check the constraint. If the constraint is INITIALLY
          IMMEDIATE, it is checked after each statement. This is the
          default. If the constraint is INITIALLY DEFERRED, it is checked
          only at the end of the transaction. The constraint check time
          can be altered with the SET CONSTRAINTS command.

   ENFORCED
          NOT ENFORCED #
          When the constraint is ENFORCED, then the database system will
          ensure that the constraint is satisfied, by checking the
          constraint at appropriate times (after each statement or at the
          end of the transaction, as appropriate). That is the default. If
          the constraint is NOT ENFORCED, the database system will not
          check the constraint. It is then up to the application code to
          ensure that the constraints are satisfied. The database system
          might still assume that the data actually satisfies the
          constraint for optimization decisions where this does not affect
          the correctness of the result.

          NOT ENFORCED constraints can be useful as documentation if the
          actual checking of the constraint at run time is too expensive.

          This is currently only supported for foreign key and CHECK
          constraints.

   USING method #
          This optional clause specifies the table access method to use to
          store the contents for the new table; the method needs be an
          access method of type TABLE. See Chapter 62 for more
          information. If this option is not specified, the default table
          access method is chosen for the new table. See
          default_table_access_method for more information.

          When creating a partition, the table access method is the access
          method of its partitioned table, if set.

   WITH ( storage_parameter [= value] [, ... ] ) #
          This clause specifies optional storage parameters for a table or
          index; see Storage Parameters below for more information. For
          backward-compatibility the WITH clause for a table can also
          include OIDS=FALSE to specify that rows of the new table should
          not contain OIDs (object identifiers), OIDS=TRUE is not
          supported anymore.

   WITHOUT OIDS #
          This is backward-compatible syntax for declaring a table WITHOUT
          OIDS, creating a table WITH OIDS is not supported anymore.

   ON COMMIT #
          The behavior of temporary tables at the end of a transaction
          block can be controlled using ON COMMIT. The three options are:

        PRESERVE ROWS #
                No special action is taken at the ends of transactions.
                This is the default behavior.

        DELETE ROWS #
                All rows in the temporary table will be deleted at the end
                of each transaction block. Essentially, an automatic
                TRUNCATE is done at each commit. When used on a
                partitioned table, this is not cascaded to its partitions.

        DROP #
                The temporary table will be dropped at the end of the
                current transaction block. When used on a partitioned
                table, this action drops its partitions and when used on
                tables with inheritance children, it drops the dependent
                children.

   TABLESPACE tablespace_name #
          The tablespace_name is the name of the tablespace in which the
          new table is to be created. If not specified, default_tablespace
          is consulted, or temp_tablespaces if the table is temporary. For
          partitioned tables, since no storage is required for the table
          itself, the tablespace specified overrides default_tablespace as
          the default tablespace to use for any newly created partitions
          when no other tablespace is explicitly specified.

   USING INDEX TABLESPACE tablespace_name #
          This clause allows selection of the tablespace in which the
          index associated with a UNIQUE, PRIMARY KEY, or EXCLUDE
          constraint will be created. If not specified, default_tablespace
          is consulted, or temp_tablespaces if the table is temporary.

Storage Parameters

   The WITH clause can specify storage parameters for tables, and for
   indexes associated with a UNIQUE, PRIMARY KEY, or EXCLUDE constraint.
   Storage parameters for indexes are documented in CREATE INDEX. The
   storage parameters currently available for tables are listed below. For
   many of these parameters, as shown, there is an additional parameter
   with the same name prefixed with toast., which controls the behavior of
   the table's secondary TOAST table, if any (see Section 66.2 for more
   information about TOAST). If a table parameter value is set and the
   equivalent toast. parameter is not, the TOAST table will use the
   table's parameter value. Specifying these parameters for partitioned
   tables is not supported, but you may specify them for individual leaf
   partitions.

   fillfactor (integer) #
          The fillfactor for a table is a percentage between 10 and 100.
          100 (complete packing) is the default. When a smaller fillfactor
          is specified, INSERT operations pack table pages only to the
          indicated percentage; the remaining space on each page is
          reserved for updating rows on that page. This gives UPDATE a
          chance to place the updated copy of a row on the same page as
          the original, which is more efficient than placing it on a
          different page, and makes heap-only tuple updates more likely.
          For a table whose entries are never updated, complete packing is
          the best choice, but in heavily updated tables smaller
          fillfactors are appropriate. This parameter cannot be set for
          TOAST tables.

   toast_tuple_target (integer) #
          The toast_tuple_target specifies the minimum tuple length
          required before we try to compress and/or move long column
          values into TOAST tables, and is also the target length we try
          to reduce the length below once toasting begins. This affects
          columns marked as External (for move), Main (for compression),
          or Extended (for both) and applies only to new tuples. There is
          no effect on existing rows. By default this parameter is set to
          allow at least 4 tuples per block, which with the default block
          size will be 2040 bytes. Valid values are between 128 bytes and
          the (block size - header), by default 8160 bytes. Changing this
          value may not be useful for very short or very long rows. Note
          that the default setting is often close to optimal, and it is
          possible that setting this parameter could have negative effects
          in some cases. This parameter cannot be set for TOAST tables.

   parallel_workers (integer) #
          This sets the number of workers that should be used to assist a
          parallel scan of this table. If not set, the system will
          determine a value based on the relation size. The actual number
          of workers chosen by the planner or by utility statements that
          use parallel scans may be less, for example due to the setting
          of max_worker_processes.

   autovacuum_enabled, toast.autovacuum_enabled (boolean) #
          Enables or disables the autovacuum daemon for a particular
          table. If true, the autovacuum daemon will perform automatic
          VACUUM and/or ANALYZE operations on this table following the
          rules discussed in Section 24.1.6. If false, this table will not
          be autovacuumed, except to prevent transaction ID wraparound.
          See Section 24.1.5 for more about wraparound prevention. Note
          that the autovacuum daemon does not run at all (except to
          prevent transaction ID wraparound) if the autovacuum parameter
          is false; setting individual tables' storage parameters does not
          override that. Therefore there is seldom much point in
          explicitly setting this storage parameter to true, only to
          false.

   vacuum_index_cleanup, toast.vacuum_index_cleanup (enum) #
          Forces or disables index cleanup when VACUUM is run on this
          table. The default value is AUTO. With OFF, index cleanup is
          disabled, with ON it is enabled, and with AUTO a decision is
          made dynamically, each time VACUUM runs. The dynamic behavior
          allows VACUUM to avoid needlessly scanning indexes to remove
          very few dead tuples. Forcibly disabling all index cleanup can
          speed up VACUUM very significantly, but may also lead to
          severely bloated indexes if table modifications are frequent.
          The INDEX_CLEANUP parameter of VACUUM, if specified, overrides
          the value of this option.

   vacuum_truncate, toast.vacuum_truncate (boolean) #
          Per-table value for vacuum_truncate parameter. The TRUNCATE
          parameter of VACUUM, if specified, overrides the value of this
          option.

   autovacuum_vacuum_threshold, toast.autovacuum_vacuum_threshold
          (integer) #
          Per-table value for autovacuum_vacuum_threshold parameter.

   autovacuum_vacuum_max_threshold, toast.autovacuum_vacuum_max_threshold
          (integer) #
          Per-table value for autovacuum_vacuum_max_threshold parameter.

   autovacuum_vacuum_scale_factor, toast.autovacuum_vacuum_scale_factor
          (floating point) #
          Per-table value for autovacuum_vacuum_scale_factor parameter.

   autovacuum_vacuum_insert_threshold,
          toast.autovacuum_vacuum_insert_threshold (integer) #
          Per-table value for autovacuum_vacuum_insert_threshold
          parameter. The special value of -1 may be used to disable insert
          vacuums on the table.

   autovacuum_vacuum_insert_scale_factor,
          toast.autovacuum_vacuum_insert_scale_factor (floating point) #
          Per-table value for autovacuum_vacuum_insert_scale_factor
          parameter.

   autovacuum_analyze_threshold (integer) #
          Per-table value for autovacuum_analyze_threshold parameter.

   autovacuum_analyze_scale_factor (floating point) #
          Per-table value for autovacuum_analyze_scale_factor parameter.

   autovacuum_vacuum_cost_delay, toast.autovacuum_vacuum_cost_delay
          (floating point) #
          Per-table value for autovacuum_vacuum_cost_delay parameter.

   autovacuum_vacuum_cost_limit, toast.autovacuum_vacuum_cost_limit
          (integer) #
          Per-table value for autovacuum_vacuum_cost_limit parameter.

   autovacuum_freeze_min_age, toast.autovacuum_freeze_min_age (integer) #
          Per-table value for vacuum_freeze_min_age parameter. Note that
          autovacuum will ignore per-table autovacuum_freeze_min_age
          parameters that are larger than half the system-wide
          autovacuum_freeze_max_age setting.

   autovacuum_freeze_max_age, toast.autovacuum_freeze_max_age (integer) #
          Per-table value for autovacuum_freeze_max_age parameter. Note
          that autovacuum will ignore per-table autovacuum_freeze_max_age
          parameters that are larger than the system-wide setting (it can
          only be set smaller).

   autovacuum_freeze_table_age, toast.autovacuum_freeze_table_age
          (integer) #
          Per-table value for vacuum_freeze_table_age parameter.

   autovacuum_multixact_freeze_min_age,
          toast.autovacuum_multixact_freeze_min_age (integer) #
          Per-table value for vacuum_multixact_freeze_min_age parameter.
          Note that autovacuum will ignore per-table
          autovacuum_multixact_freeze_min_age parameters that are larger
          than half the system-wide autovacuum_multixact_freeze_max_age
          setting.

   autovacuum_multixact_freeze_max_age,
          toast.autovacuum_multixact_freeze_max_age (integer) #
          Per-table value for autovacuum_multixact_freeze_max_age
          parameter. Note that autovacuum will ignore per-table
          autovacuum_multixact_freeze_max_age parameters that are larger
          than the system-wide setting (it can only be set smaller).

   autovacuum_multixact_freeze_table_age,
          toast.autovacuum_multixact_freeze_table_age (integer) #
          Per-table value for vacuum_multixact_freeze_table_age parameter.

   log_autovacuum_min_duration, toast.log_autovacuum_min_duration
          (integer) #
          Per-table value for log_autovacuum_min_duration parameter.

   vacuum_max_eager_freeze_failure_rate,
          toast.vacuum_max_eager_freeze_failure_rate (floating point) #
          Per-table value for vacuum_max_eager_freeze_failure_rate
          parameter.

   user_catalog_table (boolean) #
          Declare the table as an additional catalog table for purposes of
          logical replication. See Section 47.6.2 for details. This
          parameter cannot be set for TOAST tables.

Notes

   PostgreSQL automatically creates an index for each unique constraint
   and primary key constraint to enforce uniqueness. Thus, it is not
   necessary to create an index explicitly for primary key columns. (See
   CREATE INDEX for more information.)

   Unique constraints and primary keys are not inherited in the current
   implementation. This makes the combination of inheritance and unique
   constraints rather dysfunctional.

   A table cannot have more than 1600 columns. (In practice, the effective
   limit is usually lower because of tuple-length constraints.)

Examples

   Create table films and table distributors:
CREATE TABLE films (
    code        char(5) CONSTRAINT firstkey PRIMARY KEY,
    title       varchar(40) NOT NULL,
    did         integer NOT NULL,
    date_prod   date,
    kind        varchar(10),
    len         interval hour to minute
);

CREATE TABLE distributors (
     did    integer PRIMARY KEY GENERATED BY DEFAULT AS IDENTITY,
     name   varchar(40) NOT NULL CHECK (name <> '')
);

   Create a table with a 2-dimensional array:
CREATE TABLE array_int (
    vector  int[][]
);

   Define a unique table constraint for the table films. Unique table
   constraints can be defined on one or more columns of the table:
CREATE TABLE films (
    code        char(5),
    title       varchar(40),
    did         integer,
    date_prod   date,
    kind        varchar(10),
    len         interval hour to minute,
    CONSTRAINT production UNIQUE(date_prod)
);

   Define a check column constraint:
CREATE TABLE distributors (
    did     integer CHECK (did > 100),
    name    varchar(40)
);

   Define a check table constraint:
CREATE TABLE distributors (
    did     integer,
    name    varchar(40),
    CONSTRAINT con1 CHECK (did > 100 AND name <> '')
);

   Define a primary key table constraint for the table films:
CREATE TABLE films (
    code        char(5),
    title       varchar(40),
    did         integer,
    date_prod   date,
    kind        varchar(10),
    len         interval hour to minute,
    CONSTRAINT code_title PRIMARY KEY(code,title)
);

   Define a primary key constraint for table distributors. The following
   two examples are equivalent, the first using the table constraint
   syntax, the second the column constraint syntax:
CREATE TABLE distributors (
    did     integer,
    name    varchar(40),
    PRIMARY KEY(did)
);

CREATE TABLE distributors (
    did     integer PRIMARY KEY,
    name    varchar(40)
);

   Assign a literal constant default value for the column name, arrange
   for the default value of column did to be generated by selecting the
   next value of a sequence object, and make the default value of modtime
   be the time at which the row is inserted:
CREATE TABLE distributors (
    name      varchar(40) DEFAULT 'Luso Films',
    did       integer DEFAULT nextval('distributors_serial'),
    modtime   timestamp DEFAULT current_timestamp
);

   Define two NOT NULL column constraints on the table distributors, one
   of which is explicitly given a name:
CREATE TABLE distributors (
    did     integer CONSTRAINT no_null NOT NULL,
    name    varchar(40) NOT NULL
);

   Define a unique constraint for the name column:
CREATE TABLE distributors (
    did     integer,
    name    varchar(40) UNIQUE
);

   The same, specified as a table constraint:
CREATE TABLE distributors (
    did     integer,
    name    varchar(40),
    UNIQUE(name)
);

   Create the same table, specifying 70% fill factor for both the table
   and its unique index:
CREATE TABLE distributors (
    did     integer,
    name    varchar(40),
    UNIQUE(name) WITH (fillfactor=70)
)
WITH (fillfactor=70);

   Create table circles with an exclusion constraint that prevents any two
   circles from overlapping:
CREATE TABLE circles (
    c circle,
    EXCLUDE USING gist (c WITH &&)
);

   Create table cinemas in tablespace diskvol1:
CREATE TABLE cinemas (
        id serial,
        name text,
        location text
) TABLESPACE diskvol1;

   Create a composite type and a typed table:
CREATE TYPE employee_type AS (name text, salary numeric);

CREATE TABLE employees OF employee_type (
    PRIMARY KEY (name),
    salary WITH OPTIONS DEFAULT 1000
);

   Create a range partitioned table:
CREATE TABLE measurement (
    logdate         date not null,
    peaktemp        int,
    unitsales       int
) PARTITION BY RANGE (logdate);

   Create a range partitioned table with multiple columns in the partition
   key:
CREATE TABLE measurement_year_month (
    logdate         date not null,
    peaktemp        int,
    unitsales       int
) PARTITION BY RANGE (EXTRACT(YEAR FROM logdate), EXTRACT(MONTH FROM logdate));

   Create a list partitioned table:
CREATE TABLE cities (
    city_id      bigserial not null,
    name         text not null,
    population   bigint
) PARTITION BY LIST (left(lower(name), 1));

   Create a hash partitioned table:
CREATE TABLE orders (
    order_id     bigint not null,
    cust_id      bigint not null,
    status       text
) PARTITION BY HASH (order_id);

   Create partition of a range partitioned table:
CREATE TABLE measurement_y2016m07
    PARTITION OF measurement (
    unitsales DEFAULT 0
) FOR VALUES FROM ('2016-07-01') TO ('2016-08-01');

   Create a few partitions of a range partitioned table with multiple
   columns in the partition key:
CREATE TABLE measurement_ym_older
    PARTITION OF measurement_year_month
    FOR VALUES FROM (MINVALUE, MINVALUE) TO (2016, 11);

CREATE TABLE measurement_ym_y2016m11
    PARTITION OF measurement_year_month
    FOR VALUES FROM (2016, 11) TO (2016, 12);

CREATE TABLE measurement_ym_y2016m12
    PARTITION OF measurement_year_month
    FOR VALUES FROM (2016, 12) TO (2017, 01);

CREATE TABLE measurement_ym_y2017m01
    PARTITION OF measurement_year_month
    FOR VALUES FROM (2017, 01) TO (2017, 02);

   Create partition of a list partitioned table:
CREATE TABLE cities_ab
    PARTITION OF cities (
    CONSTRAINT city_id_nonzero CHECK (city_id != 0)
) FOR VALUES IN ('a', 'b');

   Create partition of a list partitioned table that is itself further
   partitioned and then add a partition to it:
CREATE TABLE cities_ab
    PARTITION OF cities (
    CONSTRAINT city_id_nonzero CHECK (city_id != 0)
) FOR VALUES IN ('a', 'b') PARTITION BY RANGE (population);

CREATE TABLE cities_ab_10000_to_100000
    PARTITION OF cities_ab FOR VALUES FROM (10000) TO (100000);

   Create partitions of a hash partitioned table:
CREATE TABLE orders_p1 PARTITION OF orders
    FOR VALUES WITH (MODULUS 4, REMAINDER 0);
CREATE TABLE orders_p2 PARTITION OF orders
    FOR VALUES WITH (MODULUS 4, REMAINDER 1);
CREATE TABLE orders_p3 PARTITION OF orders
    FOR VALUES WITH (MODULUS 4, REMAINDER 2);
CREATE TABLE orders_p4 PARTITION OF orders
    FOR VALUES WITH (MODULUS 4, REMAINDER 3);

   Create a default partition:
CREATE TABLE cities_partdef
    PARTITION OF cities DEFAULT;

Compatibility

   The CREATE TABLE command conforms to the SQL standard, with exceptions
   listed below.

Temporary Tables

   Although the syntax of CREATE TEMPORARY TABLE resembles that of the SQL
   standard, the effect is not the same. In the standard, temporary tables
   are defined just once and automatically exist (starting with empty
   contents) in every session that needs them. PostgreSQL instead requires
   each session to issue its own CREATE TEMPORARY TABLE command for each
   temporary table to be used. This allows different sessions to use the
   same temporary table name for different purposes, whereas the
   standard's approach constrains all instances of a given temporary table
   name to have the same table structure.

   The standard's definition of the behavior of temporary tables is widely
   ignored. PostgreSQL's behavior on this point is similar to that of
   several other SQL databases.

   The SQL standard also distinguishes between global and local temporary
   tables, where a local temporary table has a separate set of contents
   for each SQL module within each session, though its definition is still
   shared across sessions. Since PostgreSQL does not support SQL modules,
   this distinction is not relevant in PostgreSQL.

   For compatibility's sake, PostgreSQL will accept the GLOBAL and LOCAL
   keywords in a temporary table declaration, but they currently have no
   effect. Use of these keywords is discouraged, since future versions of
   PostgreSQL might adopt a more standard-compliant interpretation of
   their meaning.

   The ON COMMIT clause for temporary tables also resembles the SQL
   standard, but has some differences. If the ON COMMIT clause is omitted,
   SQL specifies that the default behavior is ON COMMIT DELETE ROWS.
   However, the default behavior in PostgreSQL is ON COMMIT PRESERVE ROWS.
   The ON COMMIT DROP option does not exist in SQL.

Non-Deferred Uniqueness Constraints

   When a UNIQUE or PRIMARY KEY constraint is not deferrable, PostgreSQL
   checks for uniqueness immediately whenever a row is inserted or
   modified. The SQL standard says that uniqueness should be enforced only
   at the end of the statement; this makes a difference when, for example,
   a single command updates multiple key values. To obtain
   standard-compliant behavior, declare the constraint as DEFERRABLE but
   not deferred (i.e., INITIALLY IMMEDIATE). Be aware that this can be
   significantly slower than immediate uniqueness checking.

Column Check Constraints

   The SQL standard says that CHECK column constraints can only refer to
   the column they apply to; only CHECK table constraints can refer to
   multiple columns. PostgreSQL does not enforce this restriction; it
   treats column and table check constraints alike.

EXCLUDE Constraint

   The EXCLUDE constraint type is a PostgreSQL extension.

Foreign Key Constraints

   The ability to specify column lists in the foreign key actions SET
   DEFAULT and SET NULL is a PostgreSQL extension.

   It is a PostgreSQL extension that a foreign key constraint may
   reference columns of a unique index instead of columns of a primary key
   or unique constraint.

NULL “Constraint”

   The NULL “constraint” (actually a non-constraint) is a PostgreSQL
   extension to the SQL standard that is included for compatibility with
   some other database systems (and for symmetry with the NOT NULL
   constraint). Since it is the default for any column, its presence is
   simply noise.

Constraint Naming

   The SQL standard says that table and domain constraints must have names
   that are unique across the schema containing the table or domain.
   PostgreSQL is laxer: it only requires constraint names to be unique
   across the constraints attached to a particular table or domain.
   However, this extra freedom does not exist for index-based constraints
   (UNIQUE, PRIMARY KEY, and EXCLUDE constraints), because the associated
   index is named the same as the constraint, and index names must be
   unique across all relations within the same schema.

Inheritance

   Multiple inheritance via the INHERITS clause is a PostgreSQL language
   extension. SQL:1999 and later define single inheritance using a
   different syntax and different semantics. SQL:1999-style inheritance is
   not yet supported by PostgreSQL.

Zero-Column Tables

   PostgreSQL allows a table of no columns to be created (for example,
   CREATE TABLE foo();). This is an extension from the SQL standard, which
   does not allow zero-column tables. Zero-column tables are not in
   themselves very useful, but disallowing them creates odd special cases
   for ALTER TABLE DROP COLUMN, so it seems cleaner to ignore this spec
   restriction.

Multiple Identity Columns

   PostgreSQL allows a table to have more than one identity column. The
   standard specifies that a table can have at most one identity column.
   This is relaxed mainly to give more flexibility for doing schema
   changes or migrations. Note that the INSERT command supports only one
   override clause that applies to the entire statement, so having
   multiple identity columns with different behaviors is not well
   supported.

Generated Columns

   The options STORED and VIRTUAL are not standard but are also used by
   other SQL implementations. The SQL standard does not specify the
   storage of generated columns.

LIKE Clause

   While a LIKE clause exists in the SQL standard, many of the options
   that PostgreSQL accepts for it are not in the standard, and some of the
   standard's options are not implemented by PostgreSQL.

WITH Clause

   The WITH clause is a PostgreSQL extension; storage parameters are not
   in the standard.

Tablespaces

   The PostgreSQL concept of tablespaces is not part of the standard.
   Hence, the clauses TABLESPACE and USING INDEX TABLESPACE are
   extensions.

Typed Tables

   Typed tables implement a subset of the SQL standard. According to the
   standard, a typed table has columns corresponding to the underlying
   composite type as well as one other column that is the
   “self-referencing column”. PostgreSQL does not support self-referencing
   columns explicitly.

PARTITION BY Clause

   The PARTITION BY clause is a PostgreSQL extension.

PARTITION OF Clause

   The PARTITION OF clause is a PostgreSQL extension.

See Also

   ALTER TABLE, DROP TABLE, CREATE TABLE AS, CREATE TABLESPACE, CREATE
   TYPE