Using PostgreSQL to combine two tables

Question

I have two tables inside PostgreSQL that I want to combine. They look like this:

A     B
--------
a     0
b     1
c     2

A
---
a
b
d

I want to result of the "combine" operation to look like the following:

A     B
--------
a     0
b     1
-     2
d     -

How do I accomplish this in postgres and also pure SQL? It seems that none of the JOIN operations quite accomplish this.

Gordon Linoff · Accepted Answer · 2016-12-31 18:47:29Z

2

You are looking for full join:

select t2.a, t1.b
from t1 full join
     t2
     on t1.a = t2.a;

answered Dec 31, 2016 at 18:47

Gordon Linoff

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Comments

Gurwinder Singh · Accepted Answer · 2016-12-31 18:49:38Z

0

Full outer join:

SELECT t2.a,
  t1.b
FROM table1 t1
FULL OUTER JOIN table2 t2
ON t1.a = t2.a

For more:

answered Dec 31, 2016 at 18:49

Gurwinder Singh

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