Merge paul@work.mysql.com:/home/bk/mysql-4.0 (5772a40e) · Commits · Software / OSDI20 Artifacts / mariadb

BitKeeper/etc/logging_ok

+1 −0

Original line number	Diff line number	Diff line
		@@ -49,3 +49,4 @@ zak@linux.local
		jcole@mugatu.spaceapes.com
		arjen@fred.bitbike.com
		zak@balfor.local
		miguel@hegel.local

Docs/manual.texi

+23 −18

Original line number	Diff line number	Diff line
		@@ -3187,9 +3187,10 @@ This can be handled much more efficiently by using an

		@cindex rows, locking
		@cindex locking, row-level
		Generally, you can code around row-level locking. Some cases really
		need it, but they are very few. For instance, you can use a flag
		column in the table and do something like this:
		You can generally code around row-level locking. Some situations really
		need it, but they are very few. @code{InnoDB} tables support row-level
		locking. With MyISAM, you can use a flag column in the table and do
		something like the following:

		@example
		UPDATE tbl_name SET row_flag=1 WHERE id=ID;
		@@ -6263,9 +6264,8 @@ shell> ln -s full-path-to-mysql-VERSION-OS mysql
		shell> cd mysql
		shell> scripts/mysql_install_db
		shell> chown -R root .
		shell> chown -R mysql ./data
		shell> chown -R mysql data
		shell> chgrp -R mysql .
		shell> chown -R root ./bin
		shell> bin/safe_mysqld --user=mysql &
		or
		shell> bin/mysqld_safe --user=mysql &
		@@ -6398,9 +6398,9 @@ Change ownership of binaries to @code{root} and ownership of the data
		directory to the user that you will run @code{mysqld} as:

		@example
		shell> chown -R root /usr/local/mysql
		shell> chown -R root /usr/local/mysql/.
		shell> chown -R mysql /usr/local/mysql/data
		shell> chgrp -R mysql /usr/local/mysql
		shell> chgrp -R mysql /usr/local/mysql/.
		@end example

		The first command changes the @code{owner} attribute of the files to the
		@@ -33104,6 +33104,13 @@ mysql> select user,max(salary) AS sum from users
		-> group by user HAVING sum>10;
		@end example

		@item
		The options @code{DISTINCT}, @code{DISTINCTROW} and @code{ALL} specify
		whether duplicate rows should be returned. The default is (@code{ALL}),
		all matching rows are returned. @code{DISTINCT} and @code{DISTINCTROW}
		are synonyms and specify that duplicate rows in the result set should
		be removed.

		@item
		All options beginning with @code{SQL_}, @code{STRAIGHT_JOIN}, and
		@code{HIGH_PRIORITY} are MySQL extensions to ANSI SQL.
		@@ -55415,22 +55422,20 @@ In MySQL, common tags to print (with the @code{d} option) are:
		@cindex methods, locking

		Currently MySQL only supports table locking for
		@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}).
		@code{ISAM}/@code{MyISAM} and @code{HEAP} tables,
		page-level locking for @code{BDB} tables and
		row-level locking for @code{InnoDB} tables.
		@xref{Internal locking}.
		With @code{MyISAM} tables one can freely mix @code{INSERT} and
		@code{SELECT} without locks (@code{Versioning}).

		Starting in version 3.23.33, you can analyse the table lock contention
		on your system by checking @code{Table_locks_waited} and
		@code{Table_locks_immediate} environment variables.

		Some database users claim that MySQL cannot support near the
		number of concurrent users because it lacks row-level locking. This
		may be true for some specific applications, but is not generally
		true. As always this depends totally on what the application does and what
		is the access/update pattern of the data.
		To decide if you want to use a table type with row-level locking,
		you will want to look at what the application does and what the
		select/update pattern of the data is.

		Pros for row locking:

mysql-test/r/union.result

+21 −0

Original line number	Diff line number	Diff line
		@@ -77,6 +77,8 @@ a b
		(select a,b from t1 limit 2) union all (select a,b from t2 order by a limit 1);
		a b
		1 a
		2 b
		3 c
		(select a,b from t1 limit 2) union all (select a,b from t2 order by a limit 1) order by b desc;
		a b
		3 c
		@@ -157,3 +159,22 @@ testtt
		tsestset
		1
		drop table t1;
		drop table if exists t1,t2;
		create table t1 (a int);
		create table t2 (a int);
		insert into t1 values (1),(2),(3),(4),(5);
		insert into t2 values (11),(12),(13),(14),(15);
		(select * from t1 limit 2) union (select * from t2 limit 3) limit 4;
		a
		1
		2
		11
		12
		(select * from t1 limit 2) union (select * from t2 limit 3);
		a
		1
		2
		11
		12
		13
		drop table t1,t2;

mysql-test/t/union.test

+8 −0

Original line number	Diff line number	Diff line
		@@ -77,3 +77,11 @@ SELECT pseudo1 FROM t1 WHERE pseudo='joce' UNION SELECT pseudo FROM t1 WHERE pse
		SELECT pseudo1 FROM t1 WHERE pseudo='joce' UNION ALL SELECT pseudo FROM t1 WHERE pseudo1='joce';
		SELECT pseudo1 FROM t1 WHERE pseudo='joce' UNION SELECT 1;
		drop table t1;
		drop table if exists t1,t2;
		create table t1 (a int);
		create table t2 (a int);
		insert into t1 values (1),(2),(3),(4),(5);
		insert into t2 values (11),(12),(13),(14),(15);
		(select * from t1 limit 2) union (select * from t2 limit 3) limit 4;
		(select * from t1 limit 2) union (select * from t2 limit 3);
		drop table t1,t2;

sql/sql_union.cc

+2 −0

Original line number	Diff line number	Diff line
		@@ -185,6 +185,8 @@ int mysql_union(THD thd, LEX lex,select_result *result)
		if (thd->select_limit == HA_POS_ERROR)
		thd->options&= ~OPTION_FOUND_ROWS;
		}
		else
		thd->select_limit= HA_POS_ERROR; // no limit
		if (describe)
		thd->select_limit= HA_POS_ERROR; // no limit
		res=mysql_select(thd,&result_table_list,