Question

我目前正在尝试在select语句中使用select语句。到目前为止，这很有效。但我希望它根据某些条件选择不同的东西。我的问题是将SQL语句子查询放在CASE语句的THEN部分而不是WHEN部分。所以我的例子是here。所以我想在CASE语句中放置一个select语句，该语句全部包含在子查询中。我也在使用SQL Server 2008。

以下是我原来的内容：

    SELECT DISTINCT
       WORK_ORDER.PART_ID,
       OPERATION.SEQUENCE_NO,
       OPERATION.RESOURCE_ID,
       OPERATION.SETUP_HRS,
       OPERATION.RUN_HRS,
       OPERATION.OPERATION_TYPE,
       OPERATION.RUN AS PCS_HR,
       REPLACE(CONVERT( VARCHAR(150), CONVERT(BINARY(150), OPERATION_BINARY.BITS)), CHAR(0), '') AS Specs_OPR,
       OPERATION.WORKORDER_BASE_ID,
       OPERATION.WORKORDER_LOT_ID,
       OPERATION.WORKORDER_SPLIT_ID,
       OPERATION.WORKORDER_SUB_ID,
       OPERATION.LOAD_SIZE_QTY,
       OPERATION.CALC_START_QTY,
       OPERATION.COMPLETED_QTY,
       (CEILING(OPERATION.CALC_START_QTY / OPERATION.LOAD_SIZE_QTY)) AS NUM_O_LOADS,
       ((OPERATION.CALC_START_QTY - OPERATION.COMPLETED_QTY) / OPERATION.LOAD_SIZE_QTY) AS LOADS_REMAINING,

       -- SubQuery

(
    SELECT DISTINCT
           descriptions = STUFF(
                               (
                                   SELECT ', '+CHAR(13)+PART.DESCRIPTION
                                   FROM dbo.PART
                                        JOIN REQUIREMENT ON PART.ID = REQUIREMENT.PART_ID
                                   WHERE REQUIREMENT.WORKORDER_BASE_ID = '026877'
                                         AND REQUIREMENT.OPERATION_SEQ_NO = '30'
                                   FOR XML PATH(''), TYPE
                               ).value('.[1]', 'nvarchar(max)'), 1, 2, '')
    FROM(REQUIREMENT R
         JOIN PART P ON R.PART_ID = P.ID)
) AS PART_DESCRIPTION

-- End of SubQuery

FROM OPERATION
     INNER JOIN WORK_ORDER ON OPERATION.WORKORDER_TYPE = WORK_ORDER.TYPE
                              AND OPERATION.WORKORDER_BASE_ID = WORK_ORDER.BASE_ID
                              AND OPERATION.WORKORDER_LOT_ID = WORK_ORDER.LOT_ID
                              AND OPERATION.WORKORDER_SPLIT_ID = WORK_ORDER.SPLIT_ID
                              AND OPERATION.WORKORDER_SUB_ID = WORK_ORDER.SUB_ID
     INNER JOIN OPERATION_BINARY ON OPERATION.WORKORDER_TYPE = OPERATION_BINARY.WORKORDER_TYPE
                                    AND OPERATION.WORKORDER_BASE_ID = OPERATION_BINARY.WORKORDER_BASE_ID
                                    AND OPERATION.WORKORDER_LOT_ID = OPERATION_BINARY.WORKORDER_LOT_ID
                                    AND OPERATION.WORKORDER_SPLIT_ID = OPERATION_BINARY.WORKORDER_SPLIT_ID
                                    AND OPERATION.WORKORDER_SUB_ID = OPERATION_BINARY.WORKORDER_SUB_ID
                                    AND OPERATION.SEQUENCE_NO = OPERATION_BINARY.SEQUENCE_NO
     JOIN REQUIREMENT ON REQUIREMENT.WORKORDER_BASE_ID = OPERATION.WORKORDER_BASE_ID
WHERE(REPLACE(CONVERT(VARCHAR(8000), CONVERT(BINARY(8000), OPERATION_BINARY.BITS)), CHAR(0), '') NOT LIKE '%Gupta%')
     AND OPERATION.WORKORDER_BASE_ID = '026877'
     AND WORK_ORDER.BASE_ID = '026877';

这就是我现在所拥有的但是我的Case在我的3行结果中创建了第4行的一些原因：

SELECT DISTINCT
       WORK_ORDER.PART_ID,
       OPERATION.SEQUENCE_NO,
       OPERATION.RESOURCE_ID,
       OPERATION.SETUP_HRS,
       OPERATION.RUN_HRS,
       OPERATION.OPERATION_TYPE,
       OPERATION.RUN AS PCS_HR,
       REPLACE(CONVERT( VARCHAR(150), CONVERT(BINARY(150), OPERATION_BINARY.BITS)), CHAR(0), '') AS Specs_OPR,
       OPERATION.WORKORDER_BASE_ID,
       OPERATION.WORKORDER_LOT_ID,
       OPERATION.WORKORDER_SPLIT_ID,
       OPERATION.WORKORDER_SUB_ID,
       OPERATION.LOAD_SIZE_QTY,
       OPERATION.CALC_START_QTY,
       OPERATION.COMPLETED_QTY,
       (CEILING(OPERATION.CALC_START_QTY / OPERATION.LOAD_SIZE_QTY)) AS NUM_O_LOADS,
       ((OPERATION.CALC_START_QTY - OPERATION.COMPLETED_QTY) / OPERATION.LOAD_SIZE_QTY) AS LOADS_REMAINING,

       -- SubQuery Inside Case

       CASE
           WHEN REQUIREMENT.OPERATION_SEQ_NO = '10'
                AND OPERATION.SEQUENCE_NO = '10'
           THEN
(
    SELECT DISTINCT
           descriptions = STUFF(
                               (
                                   SELECT ', '+CHAR(13)+PART.DESCRIPTION
                                   FROM dbo.PART
                                        JOIN REQUIREMENT ON PART.ID = REQUIREMENT.PART_ID
                                   WHERE REQUIREMENT.WORKORDER_BASE_ID = '026877'
                                         AND REQUIREMENT.OPERATION_SEQ_NO = '10'
                                   FOR XML PATH(''), TYPE
                               ).value('.[1]', 'nvarchar(max)'), 1, 2, '')
    FROM(REQUIREMENT R
         JOIN PART P ON R.PART_ID = P.ID)
)
       END AS DESCRIPTION

-- End of Subquery

FROM OPERATION
     INNER JOIN WORK_ORDER ON OPERATION.WORKORDER_TYPE = WORK_ORDER.TYPE
                              AND OPERATION.WORKORDER_BASE_ID = WORK_ORDER.BASE_ID
                              AND OPERATION.WORKORDER_LOT_ID = WORK_ORDER.LOT_ID
                              AND OPERATION.WORKORDER_SPLIT_ID = WORK_ORDER.SPLIT_ID
                              AND OPERATION.WORKORDER_SUB_ID = WORK_ORDER.SUB_ID
     INNER JOIN OPERATION_BINARY ON OPERATION.WORKORDER_TYPE = OPERATION_BINARY.WORKORDER_TYPE
                                    AND OPERATION.WORKORDER_BASE_ID = OPERATION_BINARY.WORKORDER_BASE_ID
                                    AND OPERATION.WORKORDER_LOT_ID = OPERATION_BINARY.WORKORDER_LOT_ID
                                    AND OPERATION.WORKORDER_SPLIT_ID = OPERATION_BINARY.WORKORDER_SPLIT_ID
                                    AND OPERATION.WORKORDER_SUB_ID = OPERATION_BINARY.WORKORDER_SUB_ID
                                    AND OPERATION.SEQUENCE_NO = OPERATION_BINARY.SEQUENCE_NO
     JOIN REQUIREMENT ON REQUIREMENT.WORKORDER_BASE_ID = OPERATION.WORKORDER_BASE_ID
WHERE(REPLACE(CONVERT(VARCHAR(8000), CONVERT(BINARY(8000), OPERATION_BINARY.BITS)), CHAR(0), '') NOT LIKE '%Gupta%')
     AND OPERATION.WORKORDER_BASE_ID = '026877'
     AND WORK_ORDER.BASE_ID = '026877';

Answer 1

我找到了解决我特定问题的方法。它只是我的where子句导致添加行。

但是要回答最初的问题，你可以在CASE中放置一个子查询选择语句。是的，你可以做到。

CASE
   WHEN condition
   THEN (select column1, from tbl join tbl2 on tbl1.column = tbl2.column)

   ELSE 
    (whatever)

END

是否可以在case语句中放入select语句？

1 个答案: