add test cases

source/libs/parser/src/parTranslater.c

@@ -1523,11 +1523,6 @@ static int32_t translateInterpFunc(STranslateContext* pCxt, SFunctionNode* pFunc
   SSelectStmt* pSelect = (SSelectStmt*)pCxt->pCurrStmt;
   SNode*       pTable = pSelect->pFromTable;
 
-  if (NULL != pTable && QUERY_NODE_REAL_TABLE != nodeType(pTable) && QUERY_NODE_TEMP_TABLE != nodeType(pTable)) {
-    return generateSyntaxErrMsgExt(&pCxt->msgBuf, TSDB_CODE_PAR_ONLY_SUPPORT_SINGLE_TABLE,
-                                   "unsupported table type for %s query", pFunc->functionName);
-  }
-
   if (pSelect->hasAggFuncs || pSelect->hasMultiRowsFunc || pSelect->hasIndefiniteRowsFunc) {
     return generateSyntaxErrMsg(&pCxt->msgBuf, TSDB_CODE_PAR_NOT_ALLOWED_FUNC);
   }

tests/system-test/2-query/interp.py

@@ -2952,6 +2952,17 @@ class TDTestCase:
         tdSql.error(f"select _irowts, _isfilled, interp(c0) from (select * from {dbname}.{stbname}) partition by tbname range('2020-02-01 00:00:00', '2020-02-01 00:00:14') every(1s) fill(null)")
         tdSql.error(f"select _irowts, _isfilled, interp(c0) from (select * from {dbname}.{ctbname1}) partition by tbname range('2020-02-01 00:00:00', '2020-02-01 00:00:14') every(1s) fill(null)")
 
+        tdSql.error(f"select _irowts, _isfilled, interp(c0) from (select * from {dbname}.{ctbname1} union select * from {dbname}.{ctbname2}) range('2020-02-01 00:00:00', '2020-02-01 00:00:14') every(1s) fill(null)")
+        tdSql.error(f"select _irowts, _isfilled, interp(c0) from (select * from {dbname}.{ctbname1} union select * from {dbname}.{ctbname2} order by ts) range('2020-02-01 00:00:00', '2020-02-01 00:00:14') every(1s) fill(null)")
+
+        tdSql.error(f"select _irowts, _isfilled, interp(c0) from (select * from {dbname}.{ctbname1} union all select * from {dbname}.{ctbname2}) range('2020-02-01 00:00:00', '2020-02-01 00:00:14') every(1s) fill(null)")
+        tdSql.error(f"select _irowts, _isfilled, interp(c0) from (select * from {dbname}.{ctbname1} union all select * from {dbname}.{ctbname2} order by ts) range('2020-02-01 00:00:00', '2020-02-01 00:00:14') every(1s) fill(null)")
+
+        tdSql.error(f"select _irowts, _isfilled, interp(c0) from (select * from {dbname}.{ctbname1} union all select * from {dbname}.{ctbname2}) range('2020-02-01 00:00:00', '2020-02-01 00:00:14') every(1s) fill(null)")
+        tdSql.error(f"select _irowts, _isfilled, interp(c0) from (select * from {dbname}.{ctbname1} union all select * from {dbname}.{ctbname2} order by ts) range('2020-02-01 00:00:00', '2020-02-01 00:00:14') every(1s) fill(null)")
+
+        tdSql.error(f"select _irowts, _isfilled, interp(c0) from (select * from (select * from {ctbname1}, {ctbname2} where {ctbname1}.ts = {ctbname2}.ts) range('2020-02-01 00:00:00', '2020-02-01 00:00:14') every(1s) fill(null)")
+
     def stop(self):
         tdSql.close()
         tdLog.success(f"{__file__} successfully executed")