postgresql - Look up in a white space separated string in Postgres -


i have character varying field in postgres containing 1-white-space-separated set of strings. e.g.:

  • --> 1 2 3 <--
  • --> apples bananas pears <--

i put --> , <-- show strings start , end (they not part of stored string itself)

i need query field find out if whole string contains word (apple instance). possible query 

select * table thefield '%apple%'

but sucks , won't scale b-tree indexes scale if pattern attached beginning of string while in case searched string positioned anywhere in field.

how recommend approaching problem?

consider database-normalization first.

while working current design, support query trigram index, pretty fast.

more details , links in closely related answer:
postgresql query performance variations

even more pattern matching , indexes in related answer on dba.se:
pattern matching like, similar or regular expressions in postgresql


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