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查询多个结果一起使用
?
?? SELECT? X.a,F.b from (select (3-2) a from dual) X,(select (4-2) b FROM dual) F;
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查询结果的表在与其他表使用
select * from (
with pro as (???????
?? SELECT distinct first_sequence???
????? FROM parametric_measure?
????? WHERE
?????????? measure_name = 'DATE' ),
bbb as (select? b.measure_name 测试参数,b.description 测试内容
????????? from pro p? inner join? parametric_measure b on (b.first_sequence = p.first_sequence and b.measure_name = 'HUMIDITY')
???? inner join parametric a on (a.handle = b.parametric_bo)?
???? INNER JOIN RESRCE C ON(A.SITE = C.SITE AND SPLIT(A.PARA_CONTEXT_GBO,2) = C.RESRCE AND A.SITE = '1000') )
???? select * from bbb)
?
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SQL中时间计算得到值
? SELECT??? ROUND(TO_NUMBER( TO_DATE('2013-07-04 05:10:28','YYYY-MM-DD hh24:mi:ss')? - TO_DATE('2013-07-04 02:58:28','YYYY-MM-DD hh24:mi:ss') ) * 24 ) SJ
???? from?? dual???? 得到小时
?
有两个日期数据START_DATE，END_DATE，欲得到这两个日期的时间差（以天，小时，分钟，秒，毫秒）：
天：
ROUND(TO_NUMBER(END_DATE - START_DATE))
小时：
ROUND(TO_NUMBER(END_DATE - START_DATE) * 24)
分钟：
ROUND(TO_NUMBER(END_DATE - START_DATE) * 24 * 60)
秒：
ROUND(TO_NUMBER(END_DATE - START_DATE) * 24 * 60 * 60)
毫秒：
ROUND(TO_NUMBER(END_DATE - START_DATE) * 24 * 60 * 60 * 60)