sql - Add unique constraint to an existing PostgreSQL index -


i have index in postgresql 9.3 database:

create index index_foos_on_bar_and_baz on foos using btree (bar, baz);

(from schema migration using ruby on rails)

the index present , made things faster. i've cleaned duplicate foos, i'd make index unique:

create unique index index_foos_on_bar_and_baz on foos using btree (bar, baz);

is there way alter existing index , make unique? or easier/faster delete existing index , create new, unique one?

there no way change index unique index. can see can change index @ alter index document.

in case need drop , create new unique index.


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