Data retrieval from disk

Post by **mark** » Mon Sep 11, 2006 12:33 pm

You don't happen to have any particularly long values for DOCID do you? Check with
"select max(length(DOCID)) from tbldoc"

skalyanaraman · Post by **skalyanaraman** » Mon Sep 11, 2006 1:45 pm

Hi,
Here is the result,

max(length(DOCID))
------------+
11

11 chars is the biggest length.

Post by **John** » Wed Sep 20, 2006 12:17 pm

If the max length of DOCID is 11 you should declare it as varchar(12), or closer to the real max length than 50, otherwise you will be using a lot of space in the compound index that is not needed. The compound index is one of the rare places that the declared size of the field is actually used, as part of the metamorph index relies on fixed sizes for efficiency. That is also why you get the variable size warning when creating it.