sql - Concatenate multiple result rows of one column into one, group by another column -

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• how concatenate strings of string field in postgresql 'group by' query? 11 answers

i'm having table this

movie   actor            1         2         3   b       4 

i want name of movie , actors in movie, , want result in format this:

movie   actorlist        1, 2, 3 

how can it?

simpler aggregate function string_agg() (postgres 9.0 or later):

select movie, string_agg(actor, ', ') actor_list   tbl group  1; 

the 1 in group 1 positional reference , shortcut group movie in case.

string_agg() expects data type text input. other types need cast explicitly (actor::text) - unless implicit cast text defined - case other character types (varchar, character, "char"), , other types.