单行子查询返回多行。在这种情况下我应该怎么做

Question

UPDATE STG_ABS_DSD_RECEIPTS_PI_WRK1 A
SET
(
    RECEIPT_HEADER_KEY,
    ORIG_ACNTNG_EFF_DATE,
    GL_DEPT_ID,
    RECEIPT_DATE,
    RECEIPT_TIME,
    TOTAL_INVOICE_COST_HDR,
    SUM_EXTENDED_COST_AMT
) =
(SELECT
    HDR_RECEIPT_HEADER_KEY,
    HDR_ORIG_ACNTNG_EFF_DATE,
    HDR_GL_DEPT_ID,
    HDR_RECEIPT_DATE,
    HDR_RECEIPT_TIME,
    HDR_SUM_TOTAL_INVOICE_COST,
    PIEDW_EXTENDED_COST_AMT
FROM
    STG_ABS_DSD_RECEIPTS_PI_WRK4 B
WHERE
    A.SUPPLIER_KEY = B.PIEDW_SUPPLIER_KEY
AND
    A.STORE_KEY = B.PIEDW_STORE_KEY
AND
    RTRIM(LTRIM(A.SUPPLIER_INVOICE_NBR,0)) = RTRIM(LTRIM(B.PIEDW_SUPPLIER_INVOICE_NBR,0))
AND
    TO_DATE(A.PIEDW_INV_TRAN_DATE,'YYYYMMDD') = B.PIEDW_INVOICE_DATE
AND
    B.HDR_FOUND_FLAG IN ('N', 'MY'))
WHERE EXISTS
    (SELECT 1 FROM STG_ABS_DSD_RECEIPTS_PI_WRK4 B
     WHERE
         A.SUPPLIER_KEY = B.PIEDW_SUPPLIER_KEY
     AND
         A.STORE_KEY = B.PIEDW_STORE_KEY
     AND
         RTRIM(LTRIM(A.SUPPLIER_INVOICE_NBR,0)) = RTRIM(LTRIM(B.PIEDW_SUPPLIER_INVOICE_NBR,0))
     AND
         TO_DATE(A.PIEDW_INV_TRAN_DATE,'YYYYMMDD') = B.PIEDW_INVOICE_DATE
     AND
         B.HDR_FOUND_FLAG IN ('N', 'MY'));

Answer 1

您应确保子查询仅通过从您正在更新的表中提供正确的连接来返回所需的行，或者如果您只想从可能返回的许多行中返回一行，则使用“WHERE ROWNUM = 1” （或其他RDBMS或Oracle 12c中的LIMIT子句）