diff --git a/BitKeeper/etc/logging_ok b/BitKeeper/etc/logging_ok index 9ffe97dff59..6efacbf4998 100644 --- a/BitKeeper/etc/logging_ok +++ b/BitKeeper/etc/logging_ok @@ -69,3 +69,4 @@ zak@balfor.local zak@linux.local salle@geopard.(none) walrus@mysql.com +zgreant@mysql.com diff --git a/Docs/manual.texi b/Docs/manual.texi index 4471f3fe14e..81759c19b7b 100644 --- a/Docs/manual.texi +++ b/Docs/manual.texi @@ -30674,12 +30674,12 @@ mysql> SELECT INTERVAL(22, 23, 30, 44, 200); @end example @end table -If you are comparing case-sensitive string with any of the standard -operators (@code{=}, @code{<>}..., but not @code{LIKE}) end space will -be ignored. +If you are comparing case-insensitive strings with any of the standard +operators (@code{=}, @code{<>}..., but not @code{LIKE}) trailing whitespace +(spaces, tabs and newlines) will be ignored. @example -mysql> SELECT "a" ="A "; +mysql> SELECT "a" ="A \n"; -> 1 @end example @@ -36874,28 +36874,26 @@ parameters to @code{FULLTEXT} in @code{CREATE/ALTER TABLE}). From version 4.0.1, @code{MySQL server} features a @code{Query Cache}. When in use, the query cache stores the text of a @code{SELECT} query -together with the corresponding result that is sent to a client. -If another identical query is received, the server can then retrieve +together with the corresponding result that was sent to the client. +If an identical query is later received, the server will retrieve the results from the query cache rather than parsing and executing the same query again. +@strong{NOTE:} The query cache does not return stale data. When data +is modified, any relevant entries in the query cache are flushed. + The query cache is extremely useful in an environment where (some) tables don't change very often and you have a lot of identical queries. This is a typical situation for many web servers that use a lot of dynamic content. -Following are some performance data for the query cache -(We got these by running the MySQL benchmark suite on a Linux Alpha -2x500 MHz with 2GB RAM and a 64MB query cache): +Below is some performance data for the query cache. (These results were +generated by running the MySQL benchmark suite on a Linux Alpha +2 x 500 MHz with 2GB RAM and a 64MB query cache): @itemize @bullet @item -If you want to disable the query cache code set @code{query_cache_size=0}. -By disabling the query cache code there is no noticeable overhead. -(query cache can be excluded from code with help of configure option -@code{--without-query-cache}) -@item -If all of the queries you're preforming are simple (such as selecting a +If all of the queries you're performing are simple (such as selecting a row from a table with one row); but still differ so that the queries can not be cached, the overhead for having the query cache active is 13%. This could be regarded as the worst case scenario. However, in real life, @@ -36905,6 +36903,11 @@ is normally significantly lower. Searches after one row in a one row table is 238% faster. This can be regarded as close to the minimum speedup to be expected for a query that is cached. +@item +If you want to disable the query cache code set @code{query_cache_size=0}. +By disabling the query cache code there is no noticeable overhead. +(query cache can be excluded from code with help of configure option +@code{--without-query-cache}) @end itemize @menu