explain_per_plan_hook

Description

Hook for EXPLAIN plugins to print extra information for each plan

Interface type

explain_per_plan_hook_type

Header

src/include/commands/explain.h

Subsystem

EXPLAIN

Initial value

NULL (no hook installed)

C interface

typedef void (*explain_per_plan_hook_type) (PlannedStmt *plannedstmt, IntoClause *into, struct ExplainState *es, const char *queryString, ParamListInfo params, QueryEnvironment *queryEnv);
extern PGDLLIMPORT explain_per_plan_hook_type explain_per_plan_hook;

Core source comments

per-plan and per-node hooks for plugins to print additional info

Allow plugins to print additional information

Call sites

src/backend/commands/explain.c:650

Core call context: src/backend/commands/explain.c:644–658

	/* Print info about serialization of output */
	if (es->serialize != EXPLAIN_SERIALIZE_NONE)
		ExplainPrintSerialize(es, &serializeMetrics);

	/* Allow plugins to print additional information */
	if (explain_per_plan_hook)
		(*explain_per_plan_hook) (plannedstmt, into, es, queryString,
								  params, queryEnv);

	/*
	 * Close down the query and free resources.  Include time for this in the
	 * total execution time (although it should be pretty minimal).
	 */
	INSTR_TIME_SET_CURRENT(starttime);

Related entries

• EXPLAIN

Documentation and source

• Interface declaration
• Core definition
• Call sites

Compare versions

PostgreSQL 17 → 18: added.

--- PostgreSQL 17
+++ PostgreSQL 18
@@ -1 +1,22 @@
-Not recorded in this version
+{
+  "facts": [
+    {
+      "label": "Interface type",
+      "value": "explain_per_plan_hook_type"
+    },
+    {
+      "label": "Header",
+      "value": "src/include/commands/explain.h"
+    },
+    {
+      "label": "Subsystem",
+      "value": "EXPLAIN"
+    },
+    {
+      "label": "Initial value",
+      "value": "NULL (no hook installed)"
+    }
+  ],
+  "signature": "typedef void (*explain_per_plan_hook_type) (PlannedStmt *plannedstmt, IntoClause *into, struct ExplainState *es, const char *queryString, ParamListInfo params, QueryEnvironment *queryEnv);\nextern PGDLLIMPORT explain_per_plan_hook_type explain_per_plan_hook;",
+  "tables": null
+}

Compares recorded interfaces and attributes. Source fingerprints and build metadata are excluded; an absent sample is not proof of the introduction or removal release.

Related entries

• ExplainOneQuery_hookExplainOneQuery_hook
• explain_get_index_name_hookexplain_get_index_name_hook
• explain_per_node_hookexplain_per_node_hook
• explain_validate_options_hookexplain_validate_options_hook