Function checkInsertTargets

src/backend/parser/parse_target.c:1012–1103

* checkInsertTargets - * generate a list of INSERT column targets if not supplied, or * test supplied column names to make sure they are in target table. * Also return an integer list of the columns' attribute numbers. */

 *	  Also return an integer list of the columns' attribute numbers.
 */
List *
checkInsertTargets(ParseState *pstate, List *cols, List **attrnos)
{
	*attrnos = NIL;

	if (cols == NIL)
	{
		/*
		 * Generate default column list for INSERT.
		 */
		int			numcol = RelationGetNumberOfAttributes(pstate->p_target_relation);

		int			i;

		for (i = 0; i < numcol; i++)
		{
			ResTarget  *col;
			Form_pg_attribute attr;

			attr = TupleDescAttr(pstate->p_target_relation->rd_att, i);

			if (attr->attisdropped)
				continue;

			col = makeNode(ResTarget);
			col->name = pstrdup(NameStr(attr->attname));
			col->indirection = NIL;
			col->val = NULL;
			col->location = -1;
			cols = lappend(cols, col);
			*attrnos = lappend_int(*attrnos, i + 1);
		}
	}
	else
	{
		/*
		 * Do initial validation of user-supplied INSERT column list.
		 */
		Bitmapset  *wholecols = NULL;
		Bitmapset  *partialcols = NULL;
		ListCell   *tl;

		foreach(tl, cols)
		{
			ResTarget  *col = (ResTarget *) lfirst(tl);
			char	   *name = col->name;
			int			attrno;

			/* Lookup column name, ereport on failure */
			attrno = attnameAttNum(pstate->p_target_relation, name, false);
			if (attrno == InvalidAttrNumber)
				ereport(ERROR,
						(errcode(ERRCODE_UNDEFINED_COLUMN),
						 errmsg("column \"%s\" of relation \"%s\" does not exist",
								name,
								RelationGetRelationName(pstate->p_target_relation)),
						 parser_errposition(pstate, col->location)));