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Diffstat (limited to 'Docs/manual.texi')
| -rw-r--r-- | Docs/manual.texi | 91 |
1 files changed, 60 insertions, 31 deletions
diff --git a/Docs/manual.texi b/Docs/manual.texi index b845b6042bf..33eaeab83e4 100644 --- a/Docs/manual.texi +++ b/Docs/manual.texi @@ -333,7 +333,7 @@ Functionality Missing from MySQL Foreign Keys -* Broken Foreign KEY:: Reasons NOT to use foreign keys +* Broken Foreign KEY:: Reasons NOT to use foreign keys constraints The MySQL Access Privilege System @@ -837,7 +837,7 @@ Changes in release 3.23.x (Recommended; beta) * News-3.23.4:: Changes in release 3.23.4 * News-3.23.3:: Changes in release 3.23.3 * News-3.23.2:: Changes in release 3.23.2 -* News-3.23.1:: Changes in release 3.23.1 +* News-3.23.1:: * News-3.23.0:: Changes in release 3.23.0 Changes in release 3.22.x @@ -10171,9 +10171,9 @@ To see when @strong{MySQL} might get stored procedures, see @ref{TODO}. @cindex keys, foreign Note that foreign keys in SQL are not used to join tables, but are used -mostly for checking referential integrity. If you want to get results from -multiple tables from a @code{SELECT} statement, you do this by joining -tables: +mostly for checking referential integrity (foreign key constraints). If +you want to get results from multiple tables from a @code{SELECT} +statement, you do this by joining tables: @example SELECT * from table1,table2 where table1.id = table2.id; @@ -10200,29 +10200,33 @@ than using foreign keys. In the near future we will extend the @code{FOREIGN KEY} implementation so that at least the information will be saved in the table specification file -and may be retrieved by @code{mysqldump} and ODBC. +and may be retrieved by @code{mysqldump} and ODBC. At a later stage we will +implement the foreign key constraints for application that can't easily be +coded to avoid them. @menu -* Broken Foreign KEY:: Reasons NOT to use foreign keys +* Broken Foreign KEY:: Reasons NOT to use foreign keys constraints @end menu @node Broken Foreign KEY, , Missing Foreign Keys, Missing Foreign Keys -@subsubsection Reasons NOT to Use Foreign Keys +@subsubsection Reasons NOT to Use Foreign Keys constraints @cindex foreign keys, reasons not to use -There are so many problems with foreign keys that we don't +There are so many problems with foreign key constraints that we don't know where to start: @itemize @bullet @item -Foreign keys make life very complicated, because the foreign key definitions -must be stored in a database and implementing them would destroy the whole -``nice approach'' of using files that can be moved, copied, and removed. +Foreign key constraints make life very complicated, because the foreign +key definitions must be stored in a database and implementing them would +destroy the whole ``nice approach'' of using files that can be moved, +copied, and removed. @item -The speed impact is terrible for @code{INSERT} and @code{UPDATE} statements, -and in this case almost all @code{FOREIGN KEY} checks are useless because you -usually insert records in the right tables in the right order, anyway. +The speed impact is terrible for @code{INSERT} and @code{UPDATE} +statements, and in this case almost all @code{FOREIGN KEY} constraint +checks are useless because you usually insert records in the right +tables in the right order, anyway. @item There is also a need to hold locks on many more tables when updating one @@ -10231,12 +10235,12 @@ MUCH faster to delete records from one table first and subsequently delete them from the other tables. @item -You can no longer restore a table by doing a full delete from -the table and then restoring all records (from a new source or from a backup). +You can no longer restore a table by doing a full delete from the table +and then restoring all records (from a new source or from a backup). @item -If you have foreign keys you can't dump and restore tables unless you do so -in a very specific order. +If you use foreign key constraints you can't dump and restore tables +unless you do so in a very specific order. @item It's very easy to do ``allowed'' circular definitions that make the @@ -10248,9 +10252,11 @@ The only nice aspect of @code{FOREIGN KEY} is that it gives ODBC and some other client programs the ability to see how a table is connected and to use this to show connection diagrams and to help in building applicatons. -@strong{MySQL} will soon store @code{FOREIGN KEY} definitions so that -a client can ask for and receive an answer about how the original connection -was made. The current @file{.frm} file format does not have any place for it. +@strong{MySQL} will soon store @code{FOREIGN KEY} definitions so that a +client can ask for and receive an answer about how the original +connection was made. The current @file{.frm} file format does not have +any place for it. At a later stage we will implement the foreign key +constraints for application that can't easily be coded to avoid them. @node Missing Views, Missing comments, Missing Foreign Keys, Missing functions @subsection Views @@ -32254,10 +32260,12 @@ this program! When started with the @code{--log-slow-queries[=file_name]} option, @code{mysqld} writes a log file containing all SQL commands that took -more than @code{long_query_time} to execute. If no file name is -given, it defaults to the name of the host machine suffixed with -@code{-slow.log}. If a file name is given, but doesn't contain a path, -the file is written in the data directory. +more than @code{long_query_time} to execute. The time to get the initial +table locks are not counted as execution time. + +If no file name is given, it defaults to the name of the host machine +suffixed with @code{-slow.log}. If a file name is given, but doesn't +contain a path, the file is written in the data directory. The slow query log can be used to find queries that takes a long time to execute and are thus candidates for optimization. @@ -37068,7 +37076,7 @@ Python module with caching. By @email{gandalf@@rosmail.com}. @item @uref{http://www.mysql.com/Downloads/Contrib/MySQLmodule-1.4.tar.gz, MySQLmodule-1.4.tar.gz} Python interface for @strong{MySQL}. By Joseph Skinner @email{joe@@earthlight.co.nz}; Modified by Joerg Senekowitsch @email{senekow@@ibm.net} -@item @uref{http://www.mysql.com/Downloads/Contrib/mysql_mex_1_1b.tar.gz, mysql_mex_1_1b.tar.gz} +@item @uref{http://www.mysql.com/Downloads/Contrib/mysql_mex_11.tar.gz, mysql_mex_1_11.tar.gz} An interface program for the Matlab program by MathWorks. The interface is done by Kimmo Uutela and John Fisher (not by Mathworks). Check @uref{http://boojum.hut.fi/~kuutela/mysqlmex.html,mysqlmex.html} @@ -37341,10 +37349,10 @@ Accounting. By Jose de Leon, @email{jdl@@thevision.net} Apache authentication module for @strong{MySQL}. By Zeev Suraski, @email{bourbon@@netvision.net.il}. -@strong{Please} register this module at: -@url{http://bourbon.netvision.net.il/mysql/mod_auth_mysql/register.html}. The -registering information is only used for statistical purposes and will -encourage further development of this module! +@c @strong{Please} register this module at: +@c @url{http://bourbon.netvision.net.il/mysql/mod_auth_mysql/register.html}. The +@c registering information is only used for statistical purposes and will +@c encourage further development of this module! @item @uref{http://www.mysql.com/Downloads/Contrib/mod_log_mysql-1.05.tar.gz, mod_log_mysql-1.05.tar.gz} @strong{MySQL} logging module for Apache. By Zeev Suraski, @@ -37495,6 +37503,7 @@ Prints the structure of every table in a database. By Thomas Wana. @item @uref{http://www.mysql.com/Downloads/Contrib/mysqlsync, mysqlsync-1.0-alpha.tar.gz}. A perl script to keep remote copies of a @strong{MySQL} database in sync with a central master copy. By Mark Jeftovic. @email{markjr@@easydns.com} + @item @uref{http://www.mysql.com/Downloads/Contrib/MySQLTutor-0.2.tar.gz, MySQLTutor}. MySQLTutor. A tutor of @strong{MySQL} for beginners @@ -37516,6 +37525,9 @@ By Elizabeth. @item @uref{http://www.mysql.com/Downloads/Contrib/mybackup} @item @uref{http://www.mswanson.com/mybackup, mybackup home page} Wrapper for mysqldump to backup all databases. By Marc Swanson. + +@item @uref{http://www.mysql.com/Downloads/Contrib/mdu.pl.gz,mdu.pl.gz} +Prints the storage usage of a @strong{MySQL} database. @end itemize @cindex RPMs, for common tools @@ -37918,6 +37930,7 @@ though, so 3.23 is not released as a stable version yet. * News-3.23.4:: Changes in release 3.23.4 * News-3.23.3:: Changes in release 3.23.3 * News-3.23.2:: Changes in release 3.23.2 +* News-3.23.1:: Changes in release 3.23.1 * News-3.23.0:: Changes in release 3.23.0 @end menu @@ -37925,6 +37938,14 @@ though, so 3.23 is not released as a stable version yet. @appendixsubsec Changes in release 3.23.26 @itemize @bullet @item +@code{LEFT JOIN} did in some case prefer a full table scan when one +didn't have a @code{WHERE} clause. +@item +When using @code{--log-slow-queries}, don't count the time waiting for a lock. +@item +Fixed bug in lock code on @code{windows} which could cause the key cache +to report that the key file was crashed even if it was ok. +@item Automatic repair of @code{MyISAM} tables if you start @code{mysqld} with @code{--myisam-recover}. @item @@ -42286,12 +42307,20 @@ Allow users to change startup options. @item Subqueries. @code{select id from t where grp in (select grp from g where u > 100)} @item +@code{INSERT SQL_CONCURRENT ...}; This will force the insert to happen at the +end of the data file if the table is in use by an select to allow +concurrent inserts. +@item +Change @code{INSERT ... SELECT} to use concurrent inserts. +@item Add range checking to @code{MERGE} tables. @item @code{SHOW OPEN TABLES} @item Port of @strong{MySQL} to BeOS. @item +Link the @code{myisampack} code into the server. +@item Add a temporary key buffer cache during @code{insert/delete/update} so that we can gracefully recover if the index file gets full. @item |