×
The internal search function is temporarily non-functional. The current search engine is no longer viable and we are researching alternatives.
As a stop gap measure, we are using Google's custom search engine service.
If you know of an easy to use, open source, search engine ... please contact support@midrange.com.
OK, 4,002,000 rows later (messed up a loop <G>) VisualExplain shows
lookup time on the order of 1 to 2 milliseconds per request.
Given you only care about existence of the row, I'd also make sure you
do the lookup so it's "covered" by the index. In SQL that simply means
not asking for any data that's not in the index itself. In classic IO
IIRC, a SETLL that is _not_ followed by a read doesn't go after the base
table, just the logical.
For example, "Select 1 from BigFile where Key1='a' and Key2='b'" would
be covered (assuming you had an index on Key1 and Key2) but "select *
from BigFile where Key1=..." wouldn't be covered since the system would
need to return fields that weren't in the index.
-Walden
As an Amazon Associate we earn from qualifying purchases.
This mailing list archive is Copyright 1997-2024 by midrange.com and David Gibbs as a compilation work. Use of the archive is restricted to research of a business or technical nature. Any other uses are prohibited. Full details are available on our policy page. If you have questions about this, please contact
[javascript protected email address].
Operating expenses for this site are earned using the Amazon Associate program and Google Adsense.
midrange.com
