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   3    The view <code class="literal">triggers</code> contains all triggers defined
   4    in the current database on tables and views that the current user owns
   5    or has some privilege other than <code class="literal">SELECT</code> on.
   6   </p><div class="table" id="id-1.7.6.61.3"><p class="title"><strong>Table 35.55. <code class="structname">triggers</code> Columns</strong></p><div class="table-contents"><table class="table" summary="triggers Columns" border="1"><colgroup><col /></colgroup><thead><tr><th class="catalog_table_entry"><p class="column_definition">
   7        Column Type
   8       </p>
   9       <p>
  10        Description
  11       </p></th></tr></thead><tbody><tr><td class="catalog_table_entry"><p class="column_definition">
  12        <code class="structfield">trigger_catalog</code> <code class="type">sql_identifier</code>
  13       </p>
  14       <p>
  15        Name of the database that contains the trigger (always the current database)
  16       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  17        <code class="structfield">trigger_schema</code> <code class="type">sql_identifier</code>
  18       </p>
  19       <p>
  20        Name of the schema that contains the trigger
  21       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  22        <code class="structfield">trigger_name</code> <code class="type">sql_identifier</code>
  23       </p>
  24       <p>
  25        Name of the trigger
  26       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  27        <code class="structfield">event_manipulation</code> <code class="type">character_data</code>
  28       </p>
  29       <p>
  30        Event that fires the trigger (<code class="literal">INSERT</code>,
  31        <code class="literal">UPDATE</code>, or <code class="literal">DELETE</code>)
  32       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  33        <code class="structfield">event_object_catalog</code> <code class="type">sql_identifier</code>
  34       </p>
  35       <p>
  36        Name of the database that contains the table that the trigger
  37        is defined on (always the current database)
  38       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  39        <code class="structfield">event_object_schema</code> <code class="type">sql_identifier</code>
  40       </p>
  41       <p>
  42        Name of the schema that contains the table that the trigger is defined on
  43       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  44        <code class="structfield">event_object_table</code> <code class="type">sql_identifier</code>
  45       </p>
  46       <p>
  47        Name of the table that the trigger is defined on
  48       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  49        <code class="structfield">action_order</code> <code class="type">cardinal_number</code>
  50       </p>
  51       <p>
  52        Firing order among triggers on the same table having the same
  53        <code class="literal">event_manipulation</code>,
  54        <code class="literal">action_timing</code>, and
  55        <code class="literal">action_orientation</code>.  In
  56        <span class="productname">PostgreSQL</span>, triggers are fired in name
  57        order, so this column reflects that.
  58       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  59        <code class="structfield">action_condition</code> <code class="type">character_data</code>
  60       </p>
  61       <p>
  62        <code class="literal">WHEN</code> condition of the trigger, null if none
  63        (also null if the table is not owned by a currently enabled
  64        role)
  65       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  66        <code class="structfield">action_statement</code> <code class="type">character_data</code>
  67       </p>
  68       <p>
  69        Statement that is executed by the trigger (currently always
  70        <code class="literal">EXECUTE FUNCTION
  71        <em class="replaceable"><code>function</code></em>(...)</code>)
  72       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  73        <code class="structfield">action_orientation</code> <code class="type">character_data</code>
  74       </p>
  75       <p>
  76        Identifies whether the trigger fires once for each processed
  77        row or once for each statement (<code class="literal">ROW</code> or
  78        <code class="literal">STATEMENT</code>)
  79       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  80        <code class="structfield">action_timing</code> <code class="type">character_data</code>
  81       </p>
  82       <p>
  83        Time at which the trigger fires (<code class="literal">BEFORE</code>,
  84        <code class="literal">AFTER</code>, or <code class="literal">INSTEAD OF</code>)
  85       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  86        <code class="structfield">action_reference_old_table</code> <code class="type">sql_identifier</code>
  87       </p>
  88       <p>
  89        Name of the <span class="quote">“<span class="quote">old</span>”</span> transition table, or null if none
  90       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  91        <code class="structfield">action_reference_new_table</code> <code class="type">sql_identifier</code>
  92       </p>
  93       <p>
  94        Name of the <span class="quote">“<span class="quote">new</span>”</span> transition table, or null if none
  95       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
  96        <code class="structfield">action_reference_old_row</code> <code class="type">sql_identifier</code>
  97       </p>
  98       <p>
  99        Applies to a feature not available in <span class="productname">PostgreSQL</span>
 100       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
 101        <code class="structfield">action_reference_new_row</code> <code class="type">sql_identifier</code>
 102       </p>
 103       <p>
 104        Applies to a feature not available in <span class="productname">PostgreSQL</span>
 105       </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition">
 106        <code class="structfield">created</code> <code class="type">time_stamp</code>
 107       </p>
 108       <p>
 109        Applies to a feature not available in <span class="productname">PostgreSQL</span>
 110       </p></td></tr></tbody></table></div></div><br class="table-break" /><p>
 111    Triggers in <span class="productname">PostgreSQL</span> have two
 112    incompatibilities with the SQL standard that affect the
 113    representation in the information schema.  First, trigger names are
 114    local to each table in <span class="productname">PostgreSQL</span>, rather
 115    than being independent schema objects.  Therefore there can be duplicate
 116    trigger names defined in one schema, so long as they belong to
 117    different tables.  (<code class="literal">trigger_catalog</code> and
 118    <code class="literal">trigger_schema</code> are really the values pertaining
 119    to the table that the trigger is defined on.)  Second, triggers can
 120    be defined to fire on multiple events in
 121    <span class="productname">PostgreSQL</span> (e.g., <code class="literal">ON INSERT OR
 122    UPDATE</code>), whereas the SQL standard only allows one.  If a
 123    trigger is defined to fire on multiple events, it is represented as
 124    multiple rows in the information schema, one for each type of
 125    event.  As a consequence of these two issues, the primary key of
 126    the view <code class="literal">triggers</code> is really
 127    <code class="literal">(trigger_catalog, trigger_schema, event_object_table,
 128    trigger_name, event_manipulation)</code> instead of
 129    <code class="literal">(trigger_catalog, trigger_schema, trigger_name)</code>,
 130    which is what the SQL standard specifies.  Nonetheless, if you
 131    define your triggers in a manner that conforms with the SQL
 132    standard (trigger names unique in the schema and only one event
 133    type per trigger), this will not affect you.
 134   </p><div class="note"><h3 class="title">Note</h3><p>
 135     Prior to <span class="productname">PostgreSQL</span> 9.1, this view's columns
 136     <code class="structfield">action_timing</code>,
 137     <code class="structfield">action_reference_old_table</code>,
 138     <code class="structfield">action_reference_new_table</code>,
 139     <code class="structfield">action_reference_old_row</code>, and
 140     <code class="structfield">action_reference_new_row</code>
 141     were named
 142     <code class="structfield">condition_timing</code>,
 143     <code class="structfield">condition_reference_old_table</code>,
 144     <code class="structfield">condition_reference_new_table</code>,
 145     <code class="structfield">condition_reference_old_row</code>, and
 146     <code class="structfield">condition_reference_new_row</code>
 147     respectively.
 148     That was how they were named in the SQL:1999 standard.
 149     The new naming conforms to SQL:2003 and later.
 150    </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="infoschema-triggered-update-columns.html" title="35.56. triggered_update_columns">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-udt-privileges.html" title="35.58. udt_privileges">Next</a></td></tr><tr><td width="40%" align="left" valign="top">35.56. <code class="literal">triggered_update_columns</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"> 35.58. <code class="literal">udt_privileges</code></td></tr></table></div></body></html>