[HACKERS] BTree index and optimizer

Hello: I am trying to find out, how is the B-tree index implemented for multiple columns? does Postgres, just concatenate the columns --- if this is the case, then how is the search performed? Also, does the optimizer choose the index, only when the constraining is

[HACKERS] BTree information

I am trying to find information regarding creation of B-tree index in postgres for variable length character data (Char/varchar type). Specifically, what pagination policy is used, does it use prefix, or any other form of compression (encoding)? Regards, VJ Anand ---(