# 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? |
