SRT_Union
priorOp = p->op==TK_ALL ? SRT_Table : SRT_Union;
case TK_UNION: op = SRT_Union; break;
rc = sqliteSelect(pParse, pPrior, SRT_Union, tab1, 0, 0, 0);
rc = sqliteSelect(pParse, p, SRT_Union, tab2, 0, 0, 0);
case SRT_Union:
if( eDest!=SRT_Union && eDest!=SRT_Except && eDest!=SRT_Discard ){
case SRT_Union: {