Scott Marlowe wrote: > On Tue, 2006-02-21 at 09:57, Ibrahim Tekin wrote: > > hi, > > i have btree index on a text type field. i want see rows which starts > > with certain characters on that field. so i write a query like this: > > > > SELECT * FROM mytable WHERE myfield LIKE 'john%' > > > > since this condition is from start of the field, query planner should > > use index to find such elements but explain command shows me it will > > do a sequential scan. > > > > is this lack of a feature or i am wrong somewhere? > > This is an artifact of how PostgreSQL handles locales other than ASCII. > > If you want such a query to use an index, you need to back up your > database, and re-initdb with --locale=C as an argument.
... or you can choose to create an index with the text_pattern_ops operator class, which would be used in a LIKE constraint regardless of locale.