In article <CAPHN3JX1YNxnGsu3q5A0wGqMMwjXMcmu8LnZ72jepE2A=t23hA@xxxxxxxxxxxxxx>, Antonio Vieiro <antonio@xxxxxxxxxxxxxxxx> writes: > Hi all, > One of my entities 'E' may be 'tagged' with an arbitrary set of 256 tags 'T'. > A first approach could be to add a M:N relationship between 'E' and 'T'. > A second way to do this could be to add a BIT(256) datatype to 'E', > setting bits to '1' if the entity is tagged with each one of the 256 > tags (i.e. using a 'bitmask' on the set of tags). > Since querying entities 'E' with a certain set of tags 'T' must be > very fast I was wondering if the second approach would be faster. What > do you think? I think the best way is to put the tags into a hstore column. With a GiST index on that column access is very fast. -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
