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File format:

frm, MYI, MYD are table structures \ Indexes \ Data files for MyISAM tables, respectively

A library in a directory
However, in MySQL version 4.0 and above,
You can use the DATA directory= "directory" or the index directory= "directory" in the CREATE table statement to specify where the storage engine holds its tables and index text Thing   Note that the directory must be specified as a full path (not a relative path). This only works on the MyISAM table in MySQL 4.0, and you do not use the--skip-symlink option. View Chapter 5.6.1.2 use symbolic links to tables.


The log file can be a file,

It can also be multiple files, producing one at a time on each system startup, with the extension. 000, incrementing

A configuration item in a system configuration file my.cnf or My.ini is determined using a file or multiple log files

Log:

Log in to MySQL terminal
Log file path
Mysql> Show variables like ' general_log_file ';
+------------------+------------------------------------+
| variable_name | Value |
+------------------+------------------------------------+
| General_log_file | /usr/local/mysql/data/localhost.log |
+------------------+------------------------------------+
1 row in Set (0.00 sec)
Error log file path
Mysql> Show variables like ' log_error ';
+---------------+------------------------------------+
| variable_name | Value |
+---------------+------------------------------------+
| Log_error | /usr/local/mysql/data/localhost.err |
+---------------+------------------------------------+
1 row in Set (0.00 sec)
Slow query log file path
Mysql> Show variables like ' slow_query_log_file ';
+---------------------+-----------------------------------------+
| variable_name | Value |
+---------------------+-----------------------------------------+
| Slow_query_log_file | /usr/local/mysql/data/localhost-slow.log |
+---------------------+-----------------------------------------+
1 row in Set (0.01 sec)

MySQL has the following types of logs:
Error log:-log-err
Query log:-log
Slow query log:-log-slow-queries
Update log:-log-update
Binary log:-log-bin


Whether the log is enabled
Mysql>show variables like ' log_% ';

How to know the current log
Mysql> Show master status;

Show binary log Entries
Mysql> show master logs;

See binary log files with Mysqlbinlog
Shell>mysqlbinlog mail-bin.000001
or Shell>mysqlbinlog mail-bin.000001 | Tail

Mysqlbinlog localhost-bin.000202 > New_file_name.log command, save the target file as a log file, you can specify a save path under a small trick to introduce, I am ready to convert the log file to find more than 2G, Wondering why MySQL didn't put the logs on a regular basis in multiple files. It turns out that MySQL has a better way to get data for a certain time period through time parameters, such as: Mysqlbinlog--start-datetime= "2010-11-20 00:00:00"--stop-datetime= " 2010-11-21 00:00:00 "

Specify the output location of the log in the configuration file.
The windows:windows configuration file is My.ini, usually under the MySQL installation directory or under C:\Windows.
The Linux:linux configuration file is my.cnf, usually in/etc.

Under Linux:

SQL code

1. # Enter in [mysqld]
2. #log
3. log-error=/usr/Local/mysql/log/error.log
4. log=/usr/Local/mysql/log/mysql.log
5. long_query_time=2
6. log-slow-queries=/usr/Local/mysql/log/slowquery.log

Under Windows:

SQL code

1. # Enter in [mysqld]
2. #log
3. log-error="E:/progra~1/easyph~1.0b1/mysql/logs/error.log"
4. log="E:/progra~1/easyph~1.0b1/mysql/logs/mysql.log"
5. long_query_time=2
6. log-slow-queries= "E:/progra~1/easyph~1.0b1/mysql/logs/slowquery.log"

Turn on Slow query
Long_query_time = 2-refers to how long the SQL executed will be log down, here is 2 seconds
log-slow-queries=/usr/local/mysql/log/slowquery.log--Log the query back to a slower statement

Log-queries-not-using-indexes = nouseindex.log--literally, log down without using the indexed query

Log=mylog.log--Record all execution statements

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