Update ORDER BY UNION function/exprssion wording (again).

diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index 3d230d8684759b10da4f53b98cba1bc5159949cc..6ce8c9108b2d187f96969d2813523629b028e3d7 100644 (file)
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -2547,7 +2547,9 @@ transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt)
        if (tllen != list_length(qry->targetList))
                ereport(ERROR,
                                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-                                errmsg("A UNION/INTERSECT/EXCEPT ORDER BY cannot use expressions or functions, only result column names")));
+                                errmsg("invalid UNION/INTERSECT/EXCEPT ORDER BY clause"),
+                                errdetail("Only result column names can be used, not expressions or functions."),
+                                errhint("Add the expression/function to every SELECT, or place the query in a FROM clause.")));
 
        qry->limitOffset = transformLimitClause(pstate, limitOffset,
                                                                                        "OFFSET");