Re: table name "unnest" specified more than once

# select

 * 

from 

unnest(array[array['a', 'b'], array['c', 'c']]), 

unnest(array[array['1', '2'], array['3', '4']]);

ERROR:  42712: table name "unnest" specified more than once

I’m trying to cross-join multiple two-dimensional arrays, expecting to retain the inner arrays. I’ve been trying for hours without luck; the ever-esoteric SQL syntax foils me at every turn.

It’s a shame I can’t get the unnest function not to just concatenate the inner arrays if I just put a bunch of them. This doesn’t strike me as optimal behavior.

For more context, I’m trying to make a system of functions to score a Texas Hold ‘Em game. So I have a card type consisting of a pair of suit and rank, and I’m tossing them about. The cross-join is so I can build all candidate hands for scoring. I’m trying to create a function I can call like this:

select

best_hands_with_river(

array[

c('H', 'K'), 

c('D', 'A')

],

array[

c('C', '2'),

c('C', 'K'),

c('S', 'K'),

c('H', 'A'),

c('C', 'A')

])

Here, c is a function that constructs a card type. Card is a ROW(varchar, varchar).

So: how do I cross-join three identical arrays of my card type?