I was looking for how can I give an alias for the table being updated
(something like UPDATE table_name table_alias SET ...), but the current
syntax doesn't allow that.
What I need is to:
fduch=# SELECT * from test order by typ, name;typ | name | x
-----+------+--- 1 | bar | 1 | baz | 1 | foo | 2 | baz | 2 | foo |
(5 rows)
fduch=# UPDATE test SET x = 't'
fduch-# where typ = 1 and exists (
fduch(# SELECT 1 from test t2
fduch(# where t2.typ = 2 and t2.name = test.name
fduch(# );
UPDATE 2
fduch=# SELECT * from test order by typ, name;typ | name | x
-----+------+--- 1 | bar | 1 | baz | t 1 | foo | t 2 | baz | 2 | foo |
(5 rows)
So I have two questions:
Q1, cognitive. Why the alias for the updated table is restricted?
Is there any reason for that or it's just not implemented?
Q2, vital. Can I be sure that the syntax I used here will work
correctly, i.e. will the "test.name" always refer the column in outer
table, not inner (t2)?
Thanks in advance.
--
Fduch M. Pravking