Function transformValuesClause

src/backend/parser/analyze.c:1563–1770

* transformValuesClause - * transforms a VALUES clause that's being used as a standalone SELECT * * We build a Query containing a VALUES RTE, rather as if one had written * SELECT * FROM (VALUES ...) AS "*VALUES*" */

 *			SELECT * FROM (VALUES ...) AS "*VALUES*"
 */
static Query *
transformValuesClause(ParseState *pstate, SelectStmt *stmt)
{
	Query	   *qry = makeNode(Query);
	List	   *exprsLists = NIL;
	List	   *coltypes = NIL;
	List	   *coltypmods = NIL;
	List	   *colcollations = NIL;
	List	  **colexprs = NULL;
	int			sublist_length = -1;
	bool		lateral = false;
	ParseNamespaceItem *nsitem;
	ListCell   *lc;
	ListCell   *lc2;
	int			i;

	qry->commandType = CMD_SELECT;

	/* Most SELECT stuff doesn't apply in a VALUES clause */
	Assert(stmt->distinctClause == NIL);
	Assert(stmt->intoClause == NULL);
	Assert(stmt->targetList == NIL);
	Assert(stmt->fromClause == NIL);
	Assert(stmt->whereClause == NULL);
	Assert(stmt->groupClause == NIL);
	Assert(stmt->havingClause == NULL);
	Assert(stmt->scatterClause == NIL);
	Assert(stmt->op == SETOP_NONE);

	/* process the WITH clause independently of all else */
	if (stmt->withClause)
	{
		qry->hasRecursive = stmt->withClause->recursive;
		qry->cteList = transformWithClause(pstate, stmt->withClause);
		qry->hasModifyingCTE = pstate->p_hasModifyingCTE;
	}

	/*
	 * For each row of VALUES, transform the raw expressions.
	 *
	 * Note that the intermediate representation we build is column-organized
	 * not row-organized.  That simplifies the type and collation processing
	 * below.
	 */
	foreach(lc, stmt->valuesLists)
	{
		List	   *sublist = (List *) lfirst(lc);

		/*
		 * Do basic expression transformation (same as a ROW() expr, but here
		 * we disallow SetToDefault)
		 */
		sublist = transformExpressionList(pstate, sublist,
										  EXPR_KIND_VALUES, false);

		/*
		 * All the sublists must be the same length, *after* transformation
		 * (which might expand '*' into multiple items).  The VALUES RTE can't