db2查询：替换“with”

我们的代码结构如下所示：

select
sampleA.columnA,
(select sampleB.columnA 
    from sampleB where sampleB.ColumnB = 'test1'),
(select sampleB.columnA 
    from sampleB where sampleB.ColumnC = 'test2')
from sampleA
join sampleB on sampleA.id = sampleB.id
where sampleA.columnB = 'test3'

发生的事情是。。如果我们只运行 从sampleB中选择sampleB.columnA，其中sampleB.ColumnB='test1' 然后返回27个结果。 类似地，它返回其他一些行，比如35行 从sampleB中选择sampleB.columnA，其中sampleB.ColumnC='test2'

但是当我们运行整个查询时，我们会得到标量错误

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我们正在使用DB2，最终希望在Jasper上运行它。。Jasper不支持“with”任何其他方式？

子查询只能返回一行，请尝试以下操作：

select sampleA.columnA,
(select sampleB.columnA from sampleB where sampleB.ColumnB = 'test1' FETCH FIRST ROWS ONLY) as columnAtest1 ,
(select sampleB.columnA from sampleB where sampleB.ColumnC = 'test2' FETCH FIRST ROWS ONLY) as columnAtest2
from sampleA 
join sampleB on sampleA.id = sampleB.id
where sampleA.columnB = 'test3'

还是这个

select sampleA.columnA,
Samplec.columnA as columnAtest1, Sampled.columnA as columnAtest2
from sampleA 
join sampleB on sampleA.id = sampleB.id
cross join (select sampleB.columnA from sampleB where sampleB.ColumnB = 'test1' FETCH FIRST ROWS ONLY) Samplec
cross join (select sampleB.columnA from sampleB where sampleB.ColumnB = 'test2' FETCH FIRST ROWS ONLY) Sampled
where sampleA.columnB = 'test3'

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JasperReports支持关键字With。我用WithWith做了几份报告，你能举个例子吗？因为我使用的是jasper studio 6.3.0，“with”用红色标记。。。我一删除'with'语句，查询就运行fineSample:date_range为SELECT add_monthsTRUNC$P{period_start}，'MM'，1*Level-1 month，Level FROM dual CONNECT BY Level，您是否试图忽略警告？如果查询是有效的，您检查了它，它也应该工作