But why? The _expression_ is not on the left side of the WHERE clause.
> Hello > > use a functional index > > http://www.postgresql.org/docs/8.4/interactive/indexes-expressional.html > > Regards > > Pavel Stehule > > 2011/8/8 - - <loh.law@xxxxxxxxxxx>: > > For a table where column col has an index, the query: > > SELECT ... FROM ... WHERE col = MD5('') > > doesn't seem to use an index but > > SELECT ... FROM ... WHERE col = 'd41d8cd98f00b204e9800998ecf8427e' > > does. > > > > Is this a gotcha? > > I'm using PostgreSQL 8.4.8 on i686-pc-linux-gnu, compiled by GCC > > gcc-4.5.real (Ubuntu/Linaro 4.5.2-8ubuntu4) 4.5.2, 32-bit > > > > > > |