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   3    The view <code class="literal">check_constraints</code> contains all check
   4    constraints, either defined on a table or on a domain, that are
   5    owned by a currently enabled role.  (The owner of the table or
   6    domain is the owner of the constraint.)
   7   </p><p>
   8    The SQL standard considers not-null constraints to be check constraints
   9    with a <code class="literal">CHECK (<em class="replaceable"><code>column_name</code></em> IS NOT
  10    NULL)</code> expression.  So not-null constraints are also included here
  11    and don't have a separate view.
  12   </p><div class="table" id="id-1.7.6.13.4"><p class="title"><strong>Table 35.7. <code class="structname">check_constraints</code> Columns</strong></p><div class="table-contents"><table class="table" summary="check_constraints Columns" border="1"><colgroup><col /></colgroup><thead><tr><th class="catalog_table_entry"><p class="column_definition">
  13        Column Type
  14       </p>
  15       <p>
  16        Description
  17       </p></th></tr></thead><tbody><tr><td class="catalog_table_entry"><p class="column_definition">
  18        <code class="structfield">constraint_catalog</code> <code class="type">sql_identifier</code>
  19       </p>
  20       <p>
  21        Name of the database containing the constraint (always the current database)
  22       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  23        <code class="structfield">constraint_schema</code> <code class="type">sql_identifier</code>
  24       </p>
  25       <p>
  26        Name of the schema containing the constraint
  27       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  28        <code class="structfield">constraint_name</code> <code class="type">sql_identifier</code>
  29       </p>
  30       <p>
  31        Name of the constraint
  32       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  33        <code class="structfield">check_clause</code> <code class="type">character_data</code>
  34       </p>
  35       <p>
  36        The check expression of the check constraint
  37       </p></td></tr></tbody></table></div></div><br class="table-break" /></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="infoschema-check-constraint-routine-usage.html" title="35.8. check_constraint_routine_usage">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="information-schema.html" title="Chapter 35. The Information Schema">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="infoschema-collations.html" title="35.10. collations">Next</a></td></tr><tr><td width="40%" align="left" valign="top">35.8. <code class="literal">check_constraint_routine_usage</code> </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"> 35.10. <code class="literal">collations</code></td></tr></table></div></body></html>