我的场景是:我在 SQL 中有两张表,一张是 Header,一张是 Detail。当在标题中删除记录时,我也想删除记录的详细信息。在实际删除详细信息之前,我会先进行一些检查。
我的问题是我在检查时根据被删除的记录加入 Header 表,不幸的是,当我这样做时,用户的语句已经删除了 Header。
如果标题不符合必要的标准,我如何防止标题被删除。标题表示例:
 Key      |  Status
 -------------------
 001      |  00
 002      |  00
 003      |  40
我的删除声明:
 DELETE FROM HEADER WHERE KEY = '003'
在我删除详细信息之前的 DELETE TRIGGER 中,我正在检查以确保 Status < 40。如果不是这种情况,我会抛出错误,我该如何为 Header 做同样的事情?
我的代码如下:
 ALTER TRIGGER [dbo].[trg_PO_DELETE]
 ON PO
 AFTER DELETE
 AS
DECLARE
    @Date                   DATETIME
    , @Who                  VARCHAR(20)
    , @ProcessedStatus      CHAR(2)
    , @ProcessingStatus     CHAR(2)
    , @ShmtType             INT
    , @POType               INT
    , @MsgNo                INT
    , @Msg                  VARCHAR(MAX)
    , @Continue             INT
SET @Date                   = CURRENT_TIMESTAMP
SET @Who                    = SYSTEM_USER
SET @ProcessedStatus        = '90'
SET @ProcessingStatus       = '40'
SET @ShmtType               = 3
SET @POType                 = 1
SET @MsgNo                  = 0
SET @Msg                    = ''
SET @Continue               = 0
IF EXISTS(SELECT 1 FROM PO(NOLOCK)
                JOIN DELETED ON PO.po_asn_number = DELETED.po_asn_number
                            AND PO.po_customer_id = DELETED.po_customer_id
                            AND PO.po_number = DELETED.po_number
                            AND PO.po_type = DELETED.po_type
                            AND PO.po_status = DELETED.po_status
            WHERE PO.po_status < @ProcessingStatus)
    BEGIN
        /*  REMOVE SHIPMENT DETAIL WHEN SHIPMENT HEADER IS DELETED  */
        DELETE PO_DETAIL
        FROM PO_DETAIL 
        JOIN DELETED ON PO_DETAIL.pd_asn_number = DELETED.po_asn_number
                    AND PO_DETAIL.pd_customer_id = DELETED.po_customer_id
                    AND PO_DETAIL.pd_po_number = DELETED.po_number
                    AND PO_DETAIL.pd_type = DELETED.po_type
        /*  REMOVE UCC FOR SHIPMENT WHEN SHIPMENT IS DELETED*/ 
        DELETE UCC
        FROM UCC
        JOIN DELETED ON UCC.cs_shipment_number = DELETED.po_asn_number
                    AND UCC.cs_po_number = DELETED.po_number
                    AND DELETED.po_type = @ShmtType
        /*  UPDATE PO LEVEL INFORMATION */
        UPDATE PO 
                SET PO.po_shipped_qty = PO.po_shipped_qty - DELETED.po_shipped_qty
                , PO.po_received_qty = PO.po_received_qty - DELETED.po_received_qty
        FROM PO
        JOIN DELETED ON PO.po_asn_number = DELETED.po_number
                    AND PO.po_number = DELETED.po_number
                    AND PO.po_customer_id = DELETED.po_customer_id
                    AND DELETED.po_type = @POType
    END
ELSE
    BEGIN
        SET @Continue = 1
        SET @MsgNo = 50000
        SET @Msg = dbo.fnc_GetMessage(@MsgNo)
    END
 IF @Continue=1  -- Error Occured
    BEGIN
      RAISERROR @MsgNo @Msg
      RETURN
    END
我认为我的问题是因为标题记录在我可以加入之前就消失了。您可能提供的任何帮助都会非常有帮助。