我正在尝试在CASE
子句中使用WHERE
语句来联接2个表。我想评估POSITION_NBR2
,如果它为空(空),那么我想加入A.POSITION_NBR2 = B.POSITION_NBR
否则我想加入A.POSITION_NBR = B.POSITION_NBR
,但是在尝试运行以下命令时出现语法错误:
UPDATE #WORKTABLE
SET SLT_MEMBER = B.NAME
FROM PS_GHS_FTE_SLT A,
PS_EMPLOYEES B,
#WORKTABLE C
WHERE
CASE WHEN A.POSITION_NBR2 <> '' THEN A.POSITION_NBR2 = B.POSITION_NBR
ELSE A.POSITION_NBR = B.POSITION_NBR
END
AND A.DEPTID COLLATE Latin1_General_BIN = C.DEPTID COLLATE Latin1_General_BIN
AND B.EMPL_STATUS = 'A'
使用适当的JOIN
语法和合理的表别名:
UPDATE WT
SET SLT_MEMBER = E.NAME
FROM PS_GHS_FTE_SLT GFS JOIN
PS_EMPLOYEES E
ON E.POSITION_NBR = (CASE WHEN GFS.POSITION_NBR2 <> '' THEN GFS.POSITION_NBR2 ELSE GFS.POSITION_NBR
END) JOIN
#WORKTABLE WT
ON GFS.DEPTID COLLATE Latin1_General_BIN = WT.DEPTID COLLATE Latin1_General_BIN
WHERE E.EMPL_STATUS = 'A';
我通常不喜欢对CASE
和ON
子句使用WHERE
。不过,在这种情况下,它只是有选择地选择一列,因此不会对我造成太大的困扰。
使用适当的JOIN
语法和合理的表别名:
UPDATE WT
SET SLT_MEMBER = E.NAME
FROM PS_GHS_FTE_SLT GFS JOIN
PS_EMPLOYEES E
ON E.POSITION_NBR = (CASE WHEN GFS.POSITION_NBR2 <> '' THEN GFS.POSITION_NBR2 ELSE GFS.POSITION_NBR
END) JOIN
#WORKTABLE WT
ON GFS.DEPTID COLLATE Latin1_General_BIN = WT.DEPTID COLLATE Latin1_General_BIN
WHERE E.EMPL_STATUS = 'A';
我通常不喜欢对CASE
和ON
子句使用WHERE
。不过,在这种情况下,它只是有选择地选择一列,因此不会对我造成太大的困扰。