单行子查询返回多行。

Question

我尝试运行折叠查询，但是它给了我‘单行子查询返回多行’的错误。

BEGIN
FOR C2 IN
(SELECT S.bom_header,
                S.sap_cage_cd,
                I.part_doc_nbr AS EIS_PART_NUMBER,
                I.cage_cd AS EIS_CAGE_CODE,
                P.ec_revision_mfg,
                (SELECT NVL (I.sap_xref_no, part_doc_nbr)
          FROM eissap.tbitem i
         WHERE i.item IN (SELECT comp_part
                            FROM eissap.tbpart_config_comp_config
                           WHERE item = comp_part))
          AS sap_xref_no,
                C.comp_config,
                C.qty_per_mfg AS EIS_MFG_QTY,
                NVL (c.unit_of_measure_cd, 'EA') EIS_MFG_UOM,
                I.item AS EIS_ITEM
  FROM TEMP_SAP_BOMS_LIST_BKP S,
       EISSAP.TBITEM I,
       EISSAP.TBPART_CONFIG_COMP_CONFIG C,
       EISSAP.TBPART P
 WHERE     (S.bom_header = I.part_doc_nbr OR S.bom_header = I.sap_xref_no)
       AND S.sap_cage_cd = I.cage_cd
       AND I.item = C.part_item
       AND I.item = P.item
       AND c.config = (SELECT MAX (c1.config)
                         FROM EISSAP.tbpart_config_comp_config c1
                        WHERE c1.part_item = C.part_item))
LOOP
INSERT INTO TEMP_SAP_BOMS T
(T.bom_header           
,T.sap_cage_cd           
,T.EIS_PART_NUMBER          
,T.EIS_CAGE_CODE               
,T.ec_revision_mfg       
,T.SAP_XREF_NO                        
,T.comp_config             
,T.EIS_MFG_QTY             
,T.EIS_MFG_UOM             
,T.EIS_ITEM)                    
SELECT C2.bom_header,
                C2.sap_cage_cd,
                C2.EIS_PART_NUMBER,
                C2.EIS_CAGE_CODE,
                C2.ec_revision_mfg,
                (SELECT NVL (C2.sap_xref_no, part_doc_nbr)
          FROM eissap.tbitem i
         WHERE I.item IN (SELECT comp_part
                            FROM eissap.tbpart_config_comp_config
                           WHERE item = comp_part))
          AS sap_xref_no,
                C2.comp_config,
                C2.EIS_MFG_QTY,
                NVL (C2.EIS_MFG_UOM, 'EA'),
                C2.EIS_ITEM
  FROM TEMP_SAP_BOMS_LIST_BKP S,
       EISSAP.TBITEM I,
       EISSAP.TBPART_CONFIG_COMP_CONFIG C,
       EISSAP.TBPART P
 WHERE     (S.bom_header = I.part_doc_nbr OR S.bom_header = I.sap_xref_no)
       AND S.sap_cage_cd = I.cage_cd
       AND I.item = C.part_item
       AND I.item = P.item
       AND c.config = (SELECT MAX (c1.config)
                         FROM EISSAP.tbpart_config_comp_config c1
                        WHERE c1.part_item = C.part_item);
   END LOOP;
END;

Answer 1

极有可能

,(SELECT NVL (I.sap_xref_no, part_doc_nbr)
          FROM eissap.tbitem i
         WHERE i.item IN (SELECT comp_part
                            FROM eissap.tbpart_config_comp_config
                           WHERE item = comp_part))  AS sap_xref_no,

返回多行(与错误所述的完全相同)。在主查询的SELECT子句中使用子查询时，它必须返回最多一行。