explain_per_plan_hook

中文定义与说明

供 EXPLAIN 插件为每个计划输出额外信息的钩子。

以下中文为本站依据所列 PostgreSQL 源码注释编译的说明。

接口声明

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;

源码说明

按计划和按节点调用的钩子，供插件输出额外信息。

允许插件输出额外信息。

调用位置

• src/backend/commands/explain.c:650

核心调用上下文：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);