Re: MAX, MIN and arrays

Colton A Smith <smith(at)cs(dot)utk(dot)edu> schrieb:

> Hi:
>
> Let's say I have a table with a column of one-dimensional arrays. What
> exactly is returned when the database is queried for a maximum from that
> particular column? The array was the greatest average value? Let's say

What du you expect?

test=# select * from foo;
id | bar
----+---------
1 | {1,2,3}
2 | {2,2,2}
3 | {3,2,1}
(3 rows)

Which row is the max()?

test=# select max(bar) from foo;
max
---------
{3,2,1}
(1 row)

It compares the first value in every array. If you wish to compare the
array depending on a other column, you can use somethink like

test=# select id, bar from foo order by bar ;
id | bar
----+---------
1 | {1,2,3}
2 | {2,2,2}
3 | {3,2,1}
(3 rows)

test=# select id, bar from foo order by bar[3] ;
id | bar
----+---------
3 | {3,2,1}
2 | {2,2,2}
1 | {1,2,3}
(3 rows)

> I have a table with a column of two-dimensional arrays. What then?

The same.

HTH, Andreas
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