You need the following tools to install a MySQL binary distribution: GNU gunzip to uncompress the distribution. A reasonable tar to unpack the distribution. GNU tar is known to work. Sun tar is known to have problems. An alternative installation method under Linux is to use RPM (RedHat Package Manager) distributions.
If you run into problems, PLEASE ALWAYS USE mysqlbug when posting questions to mysql@lists.mysql.com. Even if the problem isn't a bug, mysqlbug gathers system information that will help others solve your problem. By not using mysqlbug, you lessen the likelihood of getting a solution to your problem! You will find mysqlbug in the `bin' directory after you unpack the distribution.
The basic commands you must execute to install and use a MySQL binary distribution are:
shell> groupadd mysql shell> useradd -g mysql mysql shell> cd /usr/local shell> gunzip < /path/to/mysql-VERSION-OS.tar.gz | tar xvf - shell> ln -s mysql-VERSION-OS mysql shell> cd mysql shell> scripts/mysql_install_db shell> chown -R mysql /usr/local/mysql shell> chgrp -R mysql /usr/local/mysql shell> bin/safe_mysqld --user=mysql &
You can add new users using the bin/mysql_setpermission script if you install the DBI and Msql-Mysql-modules Perl modules. A more detailed description follows.
Pick the directory under which you want to unpack the distribution, and move into it. In the example below, we unpack the distribution under `/usr/local' and create a directory `/usr/local/mysql' into which MySQL is installed. (The following instructions therefore assume you have permission to create files in `/usr/local'. If that directory is protected, you will need to perform the installation as root.)
The type of lock being held by an application that requested it. This command returns the lock mode held by an application that was requested with the sp_getapplock procedure.
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When mysqld starts, all grant table contents are read into memory and become effective at that point. Modifications to the grant tables that you perform using GRANT, REVOKE, or SET PASSWORD are noticed by the server immediately.
If you modify the grant tables manually (using INSERT, UPDATE, etc.), you should execute a FLUSH PRIVILEGES statement or run mysqladmin flush-privileges or mysqladmin reload to tell the server to reload the grant tables. Otherwise your changes will have no effect until you restart the server. If you change the grant tables manually but forget to reload the privileges, you will be wondering why your changes don't seem to make any difference!
When the server notices that the grant tables have been changed, existing client connections are affected as follows:
Table and column privilege changes take effect with the client's next request. Database privilege changes take effect at the next USE db_name command. Global privilege changes and password changes take effect the next time the client connects.
The list below indicates some of the ways that the mysqld server uses memory. Where applicable, the name of the server variable relevant to the memory use is given:
The key buffer (variable key_buffer_size) is shared by all threads; Other buffers used by the server are allocated as needed.
Each connection uses some thread-specific space: A stack (default 64K, variable thread_stack), a connection buffer (variable net_buffer_length), and a result buffer (variable net_buffer_length). The connection buffer and result buffer are dynamically enlarged up to max_allowed_packet when needed. When a query is running, a copy of the current query string is also allocated. All threads share the same base memory. Only the compressed ISAM / MyISAM tables are memory mapped. This is because the 32-bit memory space of 4GB is not large enough for most big tables. When systems with a 64-bit address space become more common we may add general support for memory mapping. Each request doing a sequential scan over a table allocates a read buffer (variable record_buffer). All joins are done in one pass, and most joins can be done without even using a temporary table. Most temporary tables are memory-based (HEAP) tables. Temporary tables with a big record length (calculated as the sum of all column lengths) or that contain BLOB columns are stored on disk. One problem in MySQL versions before Version 3.23.2 is that if a HEAP table exceeds the size of tmp_table_size, you get the error The table tbl_name is full. In newer versions this is handled by automatically changing the in-memory (HEAP) table to a disk-based (MyISAM) table as necessary. To work around this problem, you can increase the temporary table size by setting the tmp_table_size option to mysqld, or by setting the SQL option SQL_BIG_TABLES in the client program.
In MySQL Version 3.20, the maximum size of the temporary table was record_buffer*16, so if you are using this version, you have to increase the value of record_buffer. You can also start mysqld with the --big-tables option to always store temporary tables on disk. However, this will affect the speed of many complicated queries. Most requests doing a sort allocates a sort buffer and 0-2 temporary files depending on the result set size.
Almost all parsing and calculating is
Error severity 13 indicates what?
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