Function exec_stmt_execsql

src/pl/plpgsql/src/pl_exec.c:4154–4378

---------- * exec_stmt_execsql Execute an SQL statement (possibly with INTO). * * Note: some callers rely on this not touching stmt_mcontext. If it ever * needs to use that, fix those callers to push/pop stmt_mcontext. * ---------- */

 * ----------
 */
static int
exec_stmt_execsql(PLpgSQL_execstate *estate,
				  PLpgSQL_stmt_execsql *stmt)
{
	ParamListInfo paramLI;
	long		tcount;
	int			rc;
	PLpgSQL_expr *expr = stmt->sqlstmt;
	int			too_many_rows_level = 0;

	if (plpgsql_extra_errors & PLPGSQL_XCHECK_TOOMANYROWS)
		too_many_rows_level = ERROR;
	else if (plpgsql_extra_warnings & PLPGSQL_XCHECK_TOOMANYROWS)
		too_many_rows_level = WARNING;

	/*
	 * On the first call for this statement generate the plan, and detect
	 * whether the statement is INSERT/UPDATE/DELETE
	 */
	if (expr->plan == NULL)
		exec_prepare_plan(estate, expr, CURSOR_OPT_PARALLEL_OK);

	if (!stmt->mod_stmt_set)
	{
		ListCell   *l;

		stmt->mod_stmt = false;
		foreach(l, SPI_plan_get_plan_sources(expr->plan))
		{
			CachedPlanSource *plansource = (CachedPlanSource *) lfirst(l);

			/*
			 * We could look at the raw_parse_tree, but it seems simpler to
			 * check the command tag.  Note we should *not* look at the Query
			 * tree(s), since those are the result of rewriting and could have
			 * been transmogrified into something else entirely.
			 */
			if (plansource->commandTag == CMDTAG_INSERT ||
				plansource->commandTag == CMDTAG_UPDATE ||
				plansource->commandTag == CMDTAG_DELETE)
			{
				stmt->mod_stmt = true;
				break;
			}
		}
		stmt->mod_stmt_set = true;
	}

	/*
	 * Set up ParamListInfo to pass to executor
	 */
	paramLI = setup_param_list(estate, expr);

	/*
	 * If we have INTO, then we only need one row back ... but if we have INTO
	 * STRICT or extra check too_many_rows, ask for two rows, so that we can
	 * verify the statement returns only one.  INSERT/UPDATE/DELETE are always
	 * treated strictly. Without INTO, just run the statement to completion