Question

我得到了请求的输出，该输出为我提供了我需要的所有信息。但是在输出结果中我有一个空行，但是应该将它们从输出中排除，因为它们不包含全部信息。 drXY:null和distInM:null-不应输出像下面的示例一样，它们应由坐标填充

 drXY:50.34982681,30.95430183 | fromXY:50.33421340,30.98074794 | distInM:2561
 drXY:50.35084534,30.95514488 | fromXY:50.33421340,30.98074794 | distInM:2597

这就是我所拥有的

 drXY:46.46833420,30.74011040 | fromXY:46.48067899,30.74296405 | distInM:1390
                              | fromXY:50.37433094,30.92993617 |
 drXY:50.36543655,30.92126656 | fromXY:50.36977360,30.92906177 | distInM:735

我已经尝试过了

select substring(query from '(drXY:[0-9]+\.[0-9]+,[0-9]+\.[0-9]+)') as drxy,
       substring(query from '(fromXY:[0-9]+\.[0-9]+,[0-9]+\.[0-9]+)') as fromxy,
       substring(query, '(distInM:[0-9]+)') as dist
from (
  select additional_data -> 'cd' ->> 'Query' as query
  from stat_event where
  additional_data -> 'cd' ? 'Query' and
  value is null and
  action = 'ProposalShown' and
  created between '2019-08-04' and '2019-08-05') t;

Answer 1

要使用派生值，我们可以将表达式放在CTE中，然后像正常一样使用派生列。

with (
    select substring(query from '(drXY:[0-9]+\.[0-9]+,[0-9]+\.[0-9]+)') as drxy,
           substring(query from '(fromXY:[0-9]+\.[0-9]+,[0-9]+\.[0-9]+)') as fromxy,
           substring(query, '(distInM:[0-9]+)') as dist
    from (
      select additional_data -> 'cd' ->> 'Query' as query
      from stat_event where
      additional_data -> 'cd' ? 'Query' and
      value is null and
      action = 'ProposalShown' and
      created between '2019-08-04' and '2019-08-05'
    ) t
) as derived
select *
from derived
where drxy is not null
  and fromxy is not null
  and dist is not null;

注意：如果query在插入和更新时分解成其派生列，事情将会变得更加容易和快捷。

排除具有空值的行

1 个答案: