database - Indexing array of strings column type in PostgreSql -

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is possible create index on column type array of strings. tried using gin indexes. queries not seem using indexes.

example  create table users (  name varchar(100),  groups text[], );  query: select name users any(groups) = 'engineering'.

also best way perform group on 'groups' column efficiently can give 'groups' , count.

a gin index can used:

create table users (  name varchar(100),  groups text[] );  create index idx_users on users using gin(groups);  -- disable sequential scan in test: set enable_seqscan off;  explain analyze select name users  groups @> (array['engineering']);

result:

"bitmap heap scan on users  (cost=4.26..8.27 rows=1 width=218) (actual time=0.021..0.021 rows=0 loops=1)" "  recheck cond: (groups @> '{engineering}'::text[])" "  ->  bitmap index scan on idx_users  (cost=0.00..4.26 rows=1 width=0) (actual time=0.016..0.016 rows=0 loops=1)" "        index cond: (groups @> '{engineering}'::text[])" "total runtime: 0.074 ms"

using aggregate functions on array, problem. function unnest() might help.

why don't normalize data? fix problems, including many problems didn't encouter yet.


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