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ChangeSet@stripped, 2002-02-05 11:37:33+02:00, heikki@stripped
manual.texi:
Updated general manual about InnoDB locking and CHECK TABLE
Docs/manual.texi
1.762 02/02/05 11:37:23 heikki@stripped +25 -13
Updated general manual about InnoDB locking and CHECK TABLE
# This is a BitKeeper patch. What follows are the unified diffs for the
# set of deltas contained in the patch. The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User: heikki
# Host: donna.mysql.fi
# Root: /home/heikki/mysql-4.0
--- 1.761/Docs/manual.texi Mon Feb 4 06:28:16 2002
+++ 1.762/Docs/manual.texi Tue Feb 5 11:37:23 2002
@@ -17384,7 +17384,7 @@
option = QUICK | FAST | MEDIUM | EXTENDED | CHANGED
@end example
-@code{CHECK TABLE} only works on @code{MyISAM} tables. On
+@code{CHECK TABLE} only works on @code{MyISAM} and @code{InnoDB} tables. On
@code{MyISAM} tables it's the same thing as running @code{myisamchk -m
table_name} on the table.
@@ -25842,10 +25842,17 @@
You can find a discussion about different locking methods in the appendix.
@xref{Locking methods}.
-All locking in MySQL is deadlock-free. This is managed by always
+All locking in MySQL is deadlock-free, except for @code{InnoDB} and
+@code{BDB} type tables.
+This is managed by always
requesting all needed locks at once at the beginning of a query and always
locking the tables in the same order.
+@code{InnoDB} type tables automatically acquire their row locks and
+@code{BDB} type tables
+their page locks during the processing of SQL statements, not at the start
+of the transaction.
+
The locking method MySQL uses for @code{WRITE} locks works as follows:
@itemize @bullet
@@ -25905,16 +25912,18 @@
The table locking code in MySQL is deadlock free.
MySQL uses table locking (instead of row locking or column
-locking) on all table types, except @code{BDB} tables, to achieve a very
+locking) on all table types, except @code{InnoDB} and @code{BDB} tables,
+to achieve a very
high lock speed. For large tables, table locking is much better than
row locking for most applications, but there are, of course, some
pitfalls.
For @code{InnoDB} and @code{BDB} tables, MySQL only uses table
-locking if you explicitely lock the table with @code{LOCK TABLES} or
-execute a command that will modify every row in the table, like
-@code{ALTER TABLE}. For these table types we recommend you to not use
-@code{LOCK TABLES} at all.
+locking if you explicitly lock the table with @code{LOCK TABLES}.
+For these table types we recommend you to not use
+@code{LOCK TABLES} at all, because @code{InnoDB} uses automatic
+row level locking and @code{BDB} uses page level locking to
+ensure transaction isolation.
In MySQL Version 3.23.7 and above, you can insert rows into
@code{MyISAM} tables at the same time other threads are reading from the
@@ -35217,8 +35226,8 @@
@code{RESTRICT} and @code{CASCADE} are allowed to make porting easier.
For the moment they don't do anything.
-@strong{Note}: @code{DROP TABLE} is not transaction-safe and will
-automatically commit any active transactions.
+@strong{Note}: @code{DROP TABLE} will
+automatically commit current active transaction.
@node CREATE INDEX, DROP INDEX, DROP TABLE, Data Definition
@@ -54935,8 +54944,10 @@
@cindex methods, locking
Currently MySQL only supports table locking for
-@code{ISAM}/@code{MyISAM} and @code{HEAP} tables and page level locking
-for @code{BDB} tables. @xref{Internal locking}. With @code{MyISAM}
+@code{ISAM}/@code{MyISAM} and @code{HEAP} tables.
+@code{InnoDB} tables use row level locking,
+and @code{BDB} tables page level locking. @xref{Internal locking}.
+With @code{MyISAM}
tables one can freely mix @code{INSERT} and @code{SELECT} without locks
(@code{Versioning}).
@@ -55036,8 +55047,9 @@
thing to different tables will also helps.
If you get speed problems with the table locks in MySQL, you
-may be able to solve these to convert some of your tables to @code{BDB} tables.
-@xref{BDB}.
+may be able to solve these by converting some of your tables to @code{InnoDB}
+or @code{BDB} tables.
+@xref{InnoDB}. @xref{BDB}.
The optimisation section in the manual covers a lot of different aspects of
how to tune ones application. @xref{Tips}.
| Thread |
|---|
| • bk commit into 4.0 tree | heikki | 5 Feb |
