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   2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>2.3. Creating a New Table</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="tutorial-concepts.html" title="2.2. Concepts" /><link rel="next" href="tutorial-populate.html" title="2.4. Populating a Table With Rows" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">2.3. Creating a New Table</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="tutorial-concepts.html" title="2.2. Concepts">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="tutorial-sql.html" title="Chapter 2. The SQL Language">Up</a></td><th width="60%" align="center">Chapter 2. The <acronym class="acronym">SQL</acronym> Language</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 18.0 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="tutorial-populate.html" title="2.4. Populating a Table With Rows">Next</a></td></tr></table><hr /></div><div class="sect1" id="TUTORIAL-TABLE"><div class="titlepage"><div><div><h2 class="title" style="clear: both">2.3. Creating a New Table <a href="#TUTORIAL-TABLE" class="id_link">#</a></h2></div></div></div><a id="id-1.4.4.4.2" class="indexterm"></a><p>
   3     You  can  create  a  new  table by specifying the table
   4     name, along with all column names and their types:
   5
   6 </p><pre class="programlisting">
   7 CREATE TABLE weather (
   8     city            varchar(80),
   9     temp_lo         int,           -- low temperature
  10     temp_hi         int,           -- high temperature
  11     prcp            real,          -- precipitation
  12     date            date
  13 );
  14 </pre><p>
  15
  16     You can enter this into <code class="command">psql</code> with the line
  17     breaks.  <code class="command">psql</code> will recognize that the command
  18     is not terminated until the semicolon.
  19    </p><p>
  20     White space (i.e., spaces, tabs, and newlines) can be used freely
  21     in SQL commands.  That means you can type the command aligned
  22     differently than above, or even all on one line.  Two dashes
  23     (<span class="quote">“<span class="quote"><code class="literal">--</code></span>”</span>) introduce comments.
  24     Whatever follows them is ignored up to the end of the line.  SQL
  25     is case-insensitive about key words and identifiers, except
  26     when identifiers are double-quoted to preserve the case (not done
  27     above).
  28    </p><p>
  29     <code class="type">varchar(80)</code> specifies a data type that can store
  30     arbitrary character strings up to 80 characters in length.
  31     <code class="type">int</code> is the normal integer type.  <code class="type">real</code> is
  32     a type for storing single precision floating-point numbers.
  33     <code class="type">date</code> should be self-explanatory.  (Yes, the column of
  34     type <code class="type">date</code> is also named <code class="structfield">date</code>.
  35     This might be convenient or confusing — you choose.)
  36    </p><p>
  37     <span class="productname">PostgreSQL</span> supports the standard
  38     <acronym class="acronym">SQL</acronym> types <code class="type">int</code>,
  39     <code class="type">smallint</code>, <code class="type">real</code>, <code class="type">double
  40     precision</code>, <code class="type">char(<em class="replaceable"><code>N</code></em>)</code>,
  41     <code class="type">varchar(<em class="replaceable"><code>N</code></em>)</code>, <code class="type">date</code>,
  42     <code class="type">time</code>, <code class="type">timestamp</code>, and
  43     <code class="type">interval</code>, as well as other types of general utility
  44     and a rich set of geometric types.
  45     <span class="productname">PostgreSQL</span> can be customized with an
  46     arbitrary number of user-defined data types.  Consequently, type
  47     names are not key words in the syntax, except where required to
  48     support special cases in the <acronym class="acronym">SQL</acronym> standard.
  49    </p><p>
  50     The second example will store cities and their associated
  51     geographical location:
  52 </p><pre class="programlisting">
  53 CREATE TABLE cities (
  54     name            varchar(80),
  55     location        point
  56 );
  57 </pre><p>
  58     The <code class="type">point</code> type is an example of a
  59     <span class="productname">PostgreSQL</span>-specific data type.
  60    </p><p>
  61     <a id="id-1.4.4.4.8.1" class="indexterm"></a>
  62
  63     Finally, it should be mentioned that if you don't need a table any
  64     longer or want to recreate it differently you can remove it using
  65     the following command:
  66 </p><pre class="synopsis">
  67 DROP TABLE <em class="replaceable"><code>tablename</code></em>;
  68 </pre><p>
  69    </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="tutorial-concepts.html" title="2.2. Concepts">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="tutorial-sql.html" title="Chapter 2. The SQL Language">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="tutorial-populate.html" title="2.4. Populating a Table With Rows">Next</a></td></tr><tr><td width="40%" align="left" valign="top">2.2. Concepts </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 18.0 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 2.4. Populating a Table With Rows</td></tr></table></div></body></html>