indexing - Which databases can create function-based indexes? -


I know that such indexes exist in the oracle. I can create the old version function-based index on MySQL ( Thanks, Google) and newer versions? How about PostgreSQL, SQL Server etc

I do not know the internal details of Oracle, but on postgrad expression Create an index, which can be a function:

An index field can be an expression calculated from values ​​of one or more columns of the table row. Get instant access to data based on some change Area could be. For example, an index calculated on upper (call) will allow clause WHERE upper (call) = 'JIM' to use an index. Edit

Edit: MySQL still seems to forge, see for details, besides some discussions are not very active.

DB 2 does.

MS SQL can not do this, but you can get similar effects using calculated columns; See.


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