SELECT WORKER_NO
FROM (SELECT WORKER_NO FROM INP_LINE_WORKER
WHERE LINE_NO = 'BA')
ORDER BY WORKER_NO)
UNION
(SELECT WORKER_NO FROM HIS_LINE_WORKER
WHERE LINE_NO = 'BA'
AND WORKER_LEAVING_DATETIME > '20100914121001'
ORDER BY WORKER_ARRIVAL_DATETIME ,WORKER_LEAVING_DATETIME)
无法通过,有问题吗?
FROM (SELECT WORKER_NO FROM INP_LINE_WORKER
WHERE LINE_NO = 'BA')
ORDER BY WORKER_NO)
UNION
(SELECT WORKER_NO FROM HIS_LINE_WORKER
WHERE LINE_NO = 'BA'
AND WORKER_LEAVING_DATETIME > '20100914121001'
ORDER BY WORKER_ARRIVAL_DATETIME ,WORKER_LEAVING_DATETIME)
无法通过,有问题吗?
FROM (SELECT WORKER_NO FROM INP_LINE_WORKER
WHERE LINE_NO = 'BA')
UNION
(SELECT WORKER_NO FROM HIS_LINE_WORKER
WHERE LINE_NO = 'BA'
AND WORKER_LEAVING_DATETIME > '20100914121001')
ORDER BY WORKER_NO
在外部排序
(SELECT WORKER_NO,WORKER_ARRIVAL_DATETIME ,WORKER_LEAVING_DATETIME,0 flag FROM INP_LINE_WORKER
WHERE LINE_NO = 'BA'
UNION
SELECT WORKER_NO,WORKER_ARRIVAL_DATETIME ,WORKER_LEAVING_DATETIME,1,flag FROM HIS_LINE_WORKER
WHERE LINE_NO = 'BA'
AND WORKER_LEAVING_DATETIME > '20100914121001')
order by flag,decode(flag,0,WORKER_NO,WORKER_ARRIVAL_DATETIME),decode(flag,0,0, WORKER_LEAVING_DATETIME)
1.时间格式可能不对,如果数据库存储的是date型,要to_char后再比较
2.order by 用的不对,
SELECT WORKER_NO
FROM (SELECT WORKER_NO FROM INP_LINE_WORKER
WHERE LINE_NO = 'BA')
ORDER BY WORKER_NO)
UNION
(SELECT WORKER_NO FROM
(SELECT WORKER_NO FROM HIS_LINE_WORKER
WHERE LINE_NO = 'BA'
AND WORKER_LEAVING_DATETIME > '20100914121001'
ORDER BY WORKER_ARRIVAL_DATETIME ,WORKER_LEAVING_DATETIME))
SELECT WORKER_NO
FROM (SELECT WORKER_NO FROM INP_LINE_WORKER
WHERE LINE_NO = 'BA'))
UNION
(SELECT WORKER_NO FROM HIS_LINE_WORKER
WHERE LINE_NO = 'BA'
AND WORKER_LEAVING_DATETIME > '20100914121001'
)
FROM (SELECT WORKER_NO FROM INP_LINE_WORKER
WHERE LINE_NO = 'BA'))
UNION
(SELECT WORKER_NO FROM HIS_LINE_WORKER
WHERE LINE_NO = 'BA'
AND WORKER_LEAVING_DATETIME > '20100914121001'
)和SELECT DISTINCT(WORKER_NO)
FROM (SELECT WORKER_NO FROM INP_LINE_WORKER
WHERE LINE_NO = 'BA'))
UNION ALL
(SELECT WORKER_NO FROM HIS_LINE_WORKER
WHERE LINE_NO = 'BA'
AND WORKER_LEAVING_DATETIME > '20100914121001'
)
ORDER BY WORKER_NO哪个效率好呢?
这几天我还是偶尔在看,minitoy你们几个好像是有点闲哦???经常看就你们几个在回答问题。
跟我上个月一样,没事天天逛CSDN,我也想啊!我想得红花啊 哈哈哈