On 10/2/06, Laura Stewart <[EMAIL PROTECTED]> wrote:
Hi -
In the 10.2 Doc Review of the Tuning Guide
http://wiki.apache.org/db-derby/TuningTenTwo
there is this comment:
In the file
http://db.apache.org/derby/docs/dev/tuning/rtuntransform472.html
there is a mention of rewriting queries:
"Users can work around this possibility by writing the query like
this (which is not optimizable):(country... ) LIKE ?".
But this does not mention the rationale for doing so, which could be
benefical for the users in understanding the transformation.
One thought is that specifying "(country || '')" disables the
transformation because "(country || '')" evaluates to a Concatenate
node instead of a ColumnReference, which makes the expression "not
optimizable" and thus the transformation is skipped.
Does anyone have any additional information as to why "(country ||
'')" should be specified?
Unless someone posts additional information by Monday, I will update
the documentation with the explanation above for using "(country || >
"')"
--
Laura Stewart
