I want to print 4 times the same row in PostgreSQL, how to achieve that ?
Table : mytable
Id | name
------------
1 | foo
2 | bar
3 | zzz
I want something like
Select 4x mytable.* from mytable where id=1
And the result should be
Id | name
------------
1 | foo
1 | foo
1 | foo
1 | foo
You can cross join against generate_series(1,4), which will return a table containing the numbers 1 to 4:
SELECT mytable.*
FROM mytable
CROSS JOIN generate_series(1,4) as x
WHERE id=1
For each row in your original result set, there will be one copy with 1 next to it, one with 2, and so on.
you can use generate_series.
sample:
t=# create table so48 (i int,n text);
CREATE TABLE
t=# insert into so48 select 1,'a';
INSERT 0 1
t=# insert into so48 select 2,'b';
INSERT 0 1
select:
t=# with s as (select generate_series(1,4,1) g) select so48.* from so48 join s on true where i = 1;
i | n
---+---
1 | a
1 | a
1 | a
1 | a
(4 rows)
use union all
Select mytable.* from mytable where id=1
union all Select mytable.* from mytable where id=1
union all Select mytable.* from mytable where id=1
union all Select mytable.* from mytable where id=1
Cross join should do the job
Select 4x mytable.* from mytable where id=1
cross join
(select 1 from dual union all
select 1 from dual union all
select 1 from dual union all
select 1 from dual )
from dual (and the 4x that has been copied from the pseudocode in the question).