我如何 select 来自两个表的数据

Question

我 select 从相同的 table 编辑了两个不同的数据，但我需要将这两个不同的数据合并为一个 table 作为 select。

例如我有这个：

SELECT DISTINCT db.nazev, db.skupina, db.datum_od1, db.datum_do1, db.mnozstvi, db.cena_bez_dph, db.datum_od, db.datum_do2, db.mnozstvi2, db.cena_bez_dph2 
FROM (
SELECT s.nazev as nazev, s.kod as skupina, (select (DATE '<<datum_od1>>')) as datum_od1, (select (DATE '<<datum_do1>>')) as datum_do1,  sum(f.mnozmj) as mnozstvi, sum(f.sumZkl) as cena_bez_dph FROM dpolfak as f
LEFT OUTER JOIN ddoklfak hla ON hla.iddoklfak = f.iddoklfak
LEFT OUTER JOIN ccenik c ON c.kod = f.kod
LEFT OUTER JOIN cskupzboz s ON s.idskupzboz = c.idskupzboz
where f.modul = 'FAV' and f.datvyst >= '<<datum_od1>>' and f.datvyst <= '<<datum_do1>>'
GROUP BY s.nazev, s.kod
UNION ALL
SELECT s.nazev as nazev, s.kod as skupina, (select (DATE '<<datum_od2>>')) as datum_od2, (select (DATE '<<datum_do2>>')) as datum_do2,  sum(f.mnozmj) as mnozstvi2, sum(f.sumZkl) as cena_bez_dph2 FROM dpolfak as f
LEFT OUTER JOIN ddoklfak hla ON hla.iddoklfak = f.iddoklfak
LEFT OUTER JOIN ccenik c ON c.kod = f.kod
LEFT OUTER JOIN cskupzboz s ON s.idskupzboz = c.idskupzboz
where f.modul = 'FAV' and f.datvyst >= '<<datum_od2>>' and f.datvyst <= '<<datum_do2>>'
GROUP BY s.nazev, s.kod
) db

但问题是功能 "UNION ALL" 将所有数据合并为一个，所以我需要 select 来自 table 的不同数据到新列中，你可以在主 select.

主要问题是这对函数 union all 不起作用 "db.datum_do2, db.mnozstvi2, db.cena_bez_dph2"（它仍然告诉我该列不存在）。我该如何解决？

这是我的实际结果：

nazev                   skupina   Datum       Datum        Množství Cena bez DPH
Směsi éterických olejů | SL024 | 01.12.2014 | 19.12.2014 | 1 798,00 | 208 142,79

Směsi éterických olejů | SL024 | 20.11.2014 | 07.01.2015 | 662,00   | 86 374,52

我想要这个：

nazev                   skupina   Datum       Datum        Množství Cena bez DPH  Datum 2      Datum 2       Množství 2  Cena bez DPH 2
Směsi éterických olejů | SL024 | 01.12.2014 | 19.12.2014 | 1 798,00 | 208 142,79 |20.11.2014 | 07.01.2015 | 662,00   | 86 374,52

Answer 1

如果你真的想要 UNION ALL 的不同查询的列分开，你可以这样做：

select col1, case when q = 1 then colA end, case when q = 2 then colA end,...
(select col1, colA as colA, 1 as q
 from...
 union all
 select col1, colB as colA, 2 as q
 from...
) db

或

select col1, col2 etc
(select col1, colA, null from...
 UNIOM ALL
 select col1, null, colB from...)

我如何 select 来自两个表的数据

How can i select data from two tables

sql

postgresql

select

union-all