auto_explain: Add logging of trigger execution

Author: Kyotaro HORIGUCHI
Reviewed-by: Jaime Casanova

contrib/auto_explain/auto_explain.c

@@ -25,6 +25,7 @@ static int	auto_explain_log_min_duration = -1; /* msec or -1 */
 static bool auto_explain_log_analyze = false;
 static bool auto_explain_log_verbose = false;
 static bool auto_explain_log_buffers = false;
+static bool auto_explain_log_triggers = false;
 static bool auto_explain_log_timing = false;
 static int	auto_explain_log_format = EXPLAIN_FORMAT_TEXT;
 static bool auto_explain_log_nested_statements = false;
@@ -113,6 +114,17 @@ _PG_init(void)
 							 NULL,
 							 NULL);
 
+	DefineCustomBoolVariable("auto_explain.log_triggers",
+							 "Include trigger statistics in plans.",
+							 "This has no effect unless log_analyze is also set.",
+							 &auto_explain_log_triggers,
+							 false,
+							 PGC_SUSET,
+							 0,
+							 NULL,
+							 NULL,
+							 NULL);
+
 	DefineCustomEnumVariable("auto_explain.log_format",
 							 "EXPLAIN format to be used for plan logging.",
 							 NULL,
@@ -295,6 +307,8 @@ explain_ExecutorEnd(QueryDesc *queryDesc)
 			ExplainBeginOutput(&es);
 			ExplainQueryText(&es, queryDesc);
 			ExplainPrintPlan(&es, queryDesc);
+			if (es.analyze && auto_explain_log_triggers)
+				ExplainPrintTriggers(&es, queryDesc);
 			ExplainEndOutput(&es);
 
 			/* Remove last line break */

doc/src/sgml/auto-explain.sgml

@@ -122,6 +122,24 @@ LOAD 'auto_explain';
     </listitem>
    </varlistentry>
 
+   <varlistentry>
+    <term>
+     <varname>auto_explain.log_triggers</varname> (<type>boolean</type>)
+    </term>
+    <indexterm>
+     <primary><varname>auto_explain.log_triggers</> configuration parameter</primary>
+    </indexterm>
+    <listitem>
+     <para>
+      <varname>auto_explain.log_triggers</varname> causes trigger
+      execution statistics to be included when an execution plan is logged.
+      This parameter is off by default. Only superusers can change this
+      setting. This parameter has no effect unless
+      <varname>auto_explain.log_analyze</> parameter is set.
+     </para>
+    </listitem>
+   </varlistentry>
+
    <varlistentry>
     <term>
      <varname>auto_explain.log_format</varname> (<type>enum</type>)