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6.4.3 Audit Log File Formats

The MySQL server calls the audit log plugin to write an audit record to its log file whenever an auditable event occurs. Typically the first audit record written after plugin startup contains the server description and startup options. Elements following that one represent events such as client connect and disconnect events, executed SQL statements, and so forth. Only top-level statements are logged, not statements within stored programs such as triggers or stored procedures. Contents of files referenced by statements such as LOAD DATA are not logged.

To select the log format that the audit log plugin uses to write its log file, set the audit_log_format system variable at server startup. These formats are available:

New-style XML format (audit_log_format=NEW): An XML format that has better compatibility with Oracle Audit Vault than old-style XML format. MySQL 5.7 introduced this format, which was backported to MySQL 5.6 as of MySQL 5.6.14.
Old-style XML format (audit_log_format=OLD): The original audit log format used by default in older MySQL series. MySQL 5.6 uses old-style XML format by default.

Note

Changing the value of audit_log_format can result in writing log entries in one format to an existing log file that contains entries in a different format. To avoid this issue, use the procedure described at Audit Log File Format.

Audit log file contents are not encrypted. See Section 6.4.2, “MySQL Enterprise Audit Security Considerations”.

The following sections describe the available audit logging formats:

New-Style XML Audit Log File Format

Here is a sample log file in new-style XML format (audit_log_format=NEW), reformatted slightly for readability:

<?xml version="1.0" encoding="utf-8"?>
<AUDIT>
 <AUDIT_RECORD>
  <TIMESTAMP>2017-10-16T14:06:33 UTC</TIMESTAMP>
  <RECORD_ID>1_2017-10-16T14:06:33</RECORD_ID>
  <NAME>Audit</NAME>
  <SERVER_ID>1</SERVER_ID>
  <VERSION>1</VERSION>
  <STARTUP_OPTIONS>/usr/local/mysql/bin/mysqld
    --socket=/usr/local/mysql/mysql.sock
    --port=3306</STARTUP_OPTIONS>
  <OS_VERSION>i686-Linux</OS_VERSION>
  <MYSQL_VERSION>5.6.39-log</MYSQL_VERSION>
 </AUDIT_RECORD>
 <AUDIT_RECORD>
  <TIMESTAMP>2017-10-16T14:09:38 UTC</TIMESTAMP>
  <RECORD_ID>2_2017-10-16T14:06:33</RECORD_ID>
  <NAME>Connect</NAME>
  <CONNECTION_ID>5</CONNECTION_ID>
  <STATUS>0</STATUS>
  <STATUS_CODE>0</STATUS_CODE>
  <USER>root</USER>
  <OS_LOGIN/>
  <HOST>localhost</HOST>
  <IP>127.0.0.1</IP>
  <COMMAND_CLASS>connect</COMMAND_CLASS>
  <PRIV_USER>root</PRIV_USER>
  <PROXY_USER/>
  <DB>test</DB>
 </AUDIT_RECORD>
...
 <AUDIT_RECORD>
  <TIMESTAMP>2017-10-16T14:09:38 UTC</TIMESTAMP>
  <RECORD_ID>6_2017-10-16T14:06:33</RECORD_ID>
  <NAME>Query</NAME>
  <CONNECTION_ID>5</CONNECTION_ID>
  <STATUS>0</STATUS>
  <STATUS_CODE>0</STATUS_CODE>
  <USER>root[root] @ localhost [127.0.0.1]</USER>
  <OS_LOGIN/>
  <HOST>localhost</HOST>
  <IP>127.0.0.1</IP>
  <COMMAND_CLASS>drop_table</COMMAND_CLASS>
  <SQLTEXT>DROP TABLE IF EXISTS t</SQLTEXT>
 </AUDIT_RECORD>
...
 <AUDIT_RECORD>
  <TIMESTAMP>2017-10-16T14:09:39 UTC</TIMESTAMP>
  <RECORD_ID>8_2017-10-16T14:06:33</RECORD_ID>
  <NAME>Quit</NAME>
  <CONNECTION_ID>5</CONNECTION_ID>
  <STATUS>0</STATUS>
  <STATUS_CODE>0</STATUS_CODE>
  <USER>root</USER>
  <OS_LOGIN/>
  <HOST>localhost</HOST>
  <IP>127.0.0.1</IP>
  <COMMAND_CLASS>connect</COMMAND_CLASS>
 </AUDIT_RECORD>
...
 <AUDIT_RECORD>
  <TIMESTAMP>2017-10-16T14:09:43 UTC</TIMESTAMP>
  <RECORD_ID>11_2017-10-16T14:06:33</RECORD_ID>
  <NAME>Quit</NAME>
  <CONNECTION_ID>6</CONNECTION_ID>
  <STATUS>0</STATUS>
  <STATUS_CODE>0</STATUS_CODE>
  <USER>root</USER>
  <OS_LOGIN/>
  <HOST>localhost</HOST>
  <IP>127.0.0.1</IP>
  <COMMAND_CLASS>connect</COMMAND_CLASS>
 </AUDIT_RECORD>
 <AUDIT_RECORD>
  <TIMESTAMP>2017-10-16T14:09:45 UTC</TIMESTAMP>
  <RECORD_ID>12_2017-10-16T14:06:33</RECORD_ID>
  <NAME>NoAudit</NAME>
  <SERVER_ID>1</SERVER_ID>
 </AUDIT_RECORD>
</AUDIT>

The audit log file is written as XML, using UTF-8 (up to 4 bytes per character). The root element is <AUDIT>. The root element contains <AUDIT_RECORD> elements, each of which provides information about an audited event. When the audit log plugin begins writing a new log file, it writes the XML declaration and opening <AUDIT> root element tag. When the plugin closes a log file, it writes the closing </AUDIT> root element tag. The closing tag is not present while the file is open.

Elements within <AUDIT_RECORD> elements have these characteristics:

Some elements appear in every <AUDIT_RECORD> element. Others are optional and may appear depending on the audit record type.
Order of elements within an <AUDIT_RECORD> element is not guaranteed.
Element values are not fixed length. Long values may be truncated as indicated in the element descriptions given later.
The <, >, ", and & characters are encoded as <, >, ", and &, respectively. NUL bytes (U+00) are encoded as the ? character.
Characters not valid as XML characters are encoded using numeric character references. Valid XML characters are:
```
#x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF]
```

The following elements are mandatory in every <AUDIT_RECORD> element:

<NAME>
A string representing the type of instruction that generated the audit event, such as a command that the server received from a client.
Example:
```
<NAME>Query</NAME>
```
Some common <NAME> values:
```
Audit    When auditing starts, which may be server startup time
Connect  When a client connects, also known as logging in
Query    An SQL statement (executed directly)
Prepare  Preparation of an SQL statement; usually followed by Execute
Execute  Execution of an SQL statement; usually follows Prepare
Shutdown Server shutdown
Quit     When a client disconnects
NoAudit  Auditing has been turned off
```
The possible values are Audit, Binlog Dump, Change user, Close stmt, Connect Out, Connect, Create DB, Daemon, Debug, Delayed insert, Drop DB, Execute, Fetch, Field List, Init DB, Kill, Long Data, NoAudit, Ping, Prepare, Processlist, Query, Quit, Refresh, Register Slave, Reset stmt, Set option, Shutdown, Sleep, Statistics, Table Dump, Time.
With the exception of Audit and NoAudit, these values correspond to the COM_xxx command values listed in the mysql_com.h header file. For example, Create DB and Change user correspond to COM_CREATE_DB and COM_CHANGE_USER, respectively.
<RECORD_ID>
A unique identifier for the audit record. The value is composed from a sequence number and timestamp, in the format SEQ_TIMESTAMP. When the audit log plugin opens the audit log file, it initializes the sequence number to the size of the audit log file, then increments the sequence by 1 for each record logged. The timestamp is a UTC value in YYYY-MM-DDThh:mm:ss format indicating the date and time when the audit log plugin opened the file.
Example:
```
<RECORD_ID>12_2017-10-16T14:06:33</RECORD_ID>
```
<TIMESTAMP>
A string representing a UTC value in YYYY-MM-DDThh:mm:ss UTC format indicating the date and time when the audit event was generated. For example, the event corresponding to execution of an SQL statement received from a client has a <TIMESTAMP> value occurring after the statement finishes, not when it was received.
Example:
```
<TIMESTAMP>2017-10-16T14:09:45 UTC</TIMESTAMP>
```

The following elements are optional in <AUDIT_RECORD> elements. Many of them occur only with specific <NAME> element values.

<COMMAND_CLASS>
A string that indicates the type of action performed.
Example:
```
<COMMAND_CLASS>drop_table</COMMAND_CLASS>
```
The values correspond to the Com_xxx status variables that indicate command counts; for example Com_drop_table and Com_select count DROP TABLE and SELECT statements, respectively. The following statement displays the possible names:
```
SELECT LOWER(REPLACE(VARIABLE_NAME, 'COM_', '')) AS name
FROM INFORMATION_SCHEMA.GLOBAL_STATUS
WHERE VARIABLE_NAME LIKE 'COM%'
ORDER BY name;
```
<CONNECTION_ID>
An unsigned integer representing the client connection identifier. This is the same as the value returned by the CONNECTION_ID() function within the session.
Example:
```
<CONNECTION_ID>127</CONNECTION_ID>
```
<DB>
A string representing the default database name.
Example:
```
<DB>test</DB>
```
<HOST>
A string representing the client host name.
Example:
```
<HOST>localhost</HOST>
```
<IP>
A string representing the client IP address.
Example:
```
<IP>127.0.0.1</IP>
```
<MYSQL_VERSION>
A string representing the MySQL server version. This is the same as the value of the VERSION() function or version system variable.
Example:
```
<MYSQL_VERSION>5.6.39-log</MYSQL_VERSION>
```
<OS_LOGIN>
A string representing the external user name used during the authentication process, as set by the plugin used to authenticate the client. With native (built-in) MySQL authentication, or if the plugin does not set the value, this element is empty. The value is the same as that of the external_user system variable (see Section 4.12, “Proxy Users”).
Example:
```
<OS_LOGIN>jeffrey</OS_LOGIN>
```
<OS_VERSION>
A string representing the operating system on which the server was built or is running.
Example:
```
<OS_VERSION>x86_64-Linux</OS_VERSION>
```
<PRIV_USER>
A string representing the user that the server authenticated the client as. This is the user name that the server uses for privilege checking, and may differ from the <USER> value.
Example:
```
<PRIV_USER>jeffrey</PRIV_USER>
```
<PROXY_USER>
A string representing the proxy user (see Section 4.12, “Proxy Users”). The value is empty if user proxying is not in effect.
Example:
```
<PROXY_USER>developer</PROXY_USER>
```
<SERVER_ID>
An unsigned integer representing the server ID. This is the same as the value of the server_id system variable.
Example:
```
<SERVER_ID>1</SERVER_ID>
```
<SQLTEXT>
A string representing the text of an SQL statement. The value can be empty. Long values may be truncated. The string, like the audit log file itself, is written using UTF-8 (up to 4 bytes per character), so the value may be the result of conversion. For example, the original statement might have been received from the client as an SJIS string.
Example:
```
<SQLTEXT>DELETE FROM t1</SQLTEXT>
```
<STARTUP_OPTIONS>
A string representing the options that were given on the command line or in option files when the MySQL server was started. The first option is the path to the server executable.
Example:
```
<STARTUP_OPTIONS>/usr/local/mysql/bin/mysqld
  --port=3306 --log_output=FILE</STARTUP_OPTIONS>
```
<STATUS>
An unsigned integer representing the command status: 0 for success, nonzero if an error occurred. This is the same as the value of the mysql_errno() C API function. See the description for <STATUS_CODE> for information about how it differs from <STATUS>.
The audit log does not contain the SQLSTATE value or error message. To see the associations between error codes, SQLSTATE values, and messages, see Server Error Message Reference.
Warnings are not logged.
Example:
```
<STATUS>1051</STATUS>
```
<STATUS_CODE>
An unsigned integer representing the command status: 0 for success, 1 if an error occurred.
The STATUS_CODE value differs from the STATUS value: STATUS_CODE is 0 for success and 1 for error, which is compatible with the EZ_collector consumer for Audit Vault. STATUS is the value of the mysql_errno() C API function. This is 0 for success and nonzero for error, and thus is not necessarily 1 for error.
Example:
```
<STATUS_CODE>0</STATUS_CODE>
```
<USER>
A string representing the user name sent by the client. This may differ from the <PRIV_USER> value.
Example:
```
<USER>root[root] @ localhost [127.0.0.1]</USER>
```
<VERSION>
An unsigned integer representing the version of the audit log file format.
Example:
```
<VERSION>1</VERSION>
```

Old-Style XML Audit Log File Format

Here is a sample log file in old-style XML format (audit_log_format=OLD), reformatted slightly for readability:

<?xml version="1.0" encoding="utf-8"?>
<AUDIT>
  <AUDIT_RECORD
    TIMESTAMP="2017-10-16T14:25:00 UTC"
    RECORD_ID="1_2017-10-16T14:25:00"
    NAME="Audit"
    SERVER_ID="1"
    VERSION="1"
    STARTUP_OPTIONS="--port=3306"
    OS_VERSION="i686-Linux"
    MYSQL_VERSION="5.6.39-log"/>
  <AUDIT_RECORD
    TIMESTAMP="2017-10-16T14:25:24 UTC"
    RECORD_ID="2_2017-10-16T14:25:00"
    NAME="Connect"
    CONNECTION_ID="4"
    STATUS="0"
    STATUS_CODE="0"
    USER="root"
    OS_LOGIN=""
    HOST="localhost"
    IP="127.0.0.1"
    COMMAND_CLASS="connect"
    PRIV_USER="root"
    PROXY_USER=""
    DB="test"/>
...
  <AUDIT_RECORD
    TIMESTAMP="2017-10-16T14:25:24 UTC"
    RECORD_ID="6_2017-10-16T14:25:00"
    NAME="Query"
    CONNECTION_ID="4"
    STATUS="0"
    STATUS_CODE="0"
    USER="root[root] @ localhost [127.0.0.1]"
    OS_LOGIN=""
    HOST="localhost"
    IP="127.0.0.1"
    COMMAND_CLASS="drop_table"
    SQLTEXT="DROP TABLE IF EXISTS t"/>
...
  <AUDIT_RECORD
    TIMESTAMP="2017-10-16T14:25:24 UTC"
    RECORD_ID="8_2017-10-16T14:25:00"
    NAME="Quit"
    CONNECTION_ID="4"
    STATUS="0"
    STATUS_CODE="0"
    USER="root"
    OS_LOGIN=""
    HOST="localhost"
    IP="127.0.0.1"
    COMMAND_CLASS="connect"
  <AUDIT_RECORD
    TIMESTAMP="2017-10-16T14:25:32 UTC"
    RECORD_ID="12_2017-10-16T14:25:00"
    NAME="NoAudit"
    SERVER_ID="1"/>
</AUDIT>

Attributes of <AUDIT_RECORD> elements have these characteristics:

Some attributes appear in every <AUDIT_RECORD> element. Others are optional and may appear depending on the audit record type.
Order of attributes within an <AUDIT_RECORD> element is not guaranteed.
Attribute values are not fixed length. Long values may be truncated as indicated in the attribute descriptions given later.
The <, >, ", and & characters are encoded as <, >, ", and &, respectively. NUL bytes (U+00) are encoded as the ? character.
Characters not valid as XML characters are encoded using numeric character references. Valid XML characters are:
```
#x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF]
```

The following attributes are mandatory in every <AUDIT_RECORD> element:

NAME
A string representing the type of instruction that generated the audit event, such as a command that the server received from a client.
Example: NAME="Query"
Some common NAME values:
```
Audit    When auditing starts, which may be server startup time
Connect  When a client connects, also known as logging in
Query    An SQL statement (executed directly)
Prepare  Preparation of an SQL statement; usually followed by Execute
Execute  Execution of an SQL statement; usually follows Prepare
Shutdown Server shutdown
Quit     When a client disconnects
NoAudit  Auditing has been turned off
```
The possible values are Audit, Binlog Dump, Change user, Close stmt, Connect Out, Connect, Create DB, Daemon, Debug, Delayed insert, Drop DB, Execute, Fetch, Field List, Init DB, Kill, Long Data, NoAudit, Ping, Prepare, Processlist, Query, Quit, Refresh, Register Slave, Reset stmt, Set option, Shutdown, Sleep, Statistics, Table Dump, Time.
With the exception of "Audit" and "NoAudit", these values correspond to the COM_xxx command values listed in the mysql_com.h header file. For example, "Create DB" and "Change user" correspond to COM_CREATE_DB and COM_CHANGE_USER, respectively.
RECORD_ID
A unique identifier for the audit record. The value is composed from a sequence number and timestamp, in the format SEQ_TIMESTAMP. When the audit log plugin opens the audit log file, it initializes the sequence number to the size of the audit log file, then increments the sequence by 1 for each record logged. The timestamp is a UTC value in YYYY-MM-DDThh:mm:ss format indicating the date and time when the audit log plugin opened the file.
Example: RECORD_ID="12_2017-10-16T14:25:00"
TIMESTAMP
A string representing a UTC value in YYYY-MM-DDThh:mm:ss UTC format indicating the date and time when the audit event was generated. For example, the event corresponding to execution of an SQL statement received from a client has a TIMESTAMP value occurring after the statement finishes, not when it was received.
Example: TIMESTAMP="2017-10-16T14:25:32 UTC"

The following attributes are optional in <AUDIT_RECORD> elements. Many of them occur only for elements with specific values of the NAME attribute.

COMMAND_CLASS
A string that indicates the type of action performed.
Example: COMMAND_CLASS="drop_table"
The values correspond to the Com_xxx status variables that indicate command counts; for example Com_drop_table and Com_select count DROP TABLE and SELECT statements, respectively. The following statement displays the possible names:
```
SELECT LOWER(REPLACE(VARIABLE_NAME, 'COM_', '')) AS name
FROM INFORMATION_SCHEMA.GLOBAL_STATUS
WHERE VARIABLE_NAME LIKE 'COM%'
ORDER BY name;
```
CONNECTION_ID
An unsigned integer representing the client connection identifier. This is the same as the value returned by the CONNECTION_ID() function within the session.
Example: CONNECTION_ID="127"
DB
A string representing the default database name.
Example: DB="test"
HOST
A string representing the client host name.
Example: HOST="localhost"
IP
A string representing the client IP address.
Example: IP="127.0.0.1"
MYSQL_VERSION
A string representing the MySQL server version. This is the same as the value of the VERSION() function or version system variable.
Example: MYSQL_VERSION="5.6.39-log"
OS_LOGIN
A string representing the external user name used during the authentication process, as set by the plugin used to authenticate the client. With native (built-in) MySQL authentication, or if the plugin does not set the value, this attribute is empty. The value is the same as that of the external_user system variable (see Section 4.12, “Proxy Users”).
Example: OS_LOGIN="jeffrey"
OS_VERSION
A string representing the operating system on which the server was built or is running.
Example: OS_VERSION="x86_64-Linux"
PRIV_USER
A string representing the user that the server authenticated the client as. This is the user name that the server uses for privilege checking, and it may differ from the USER value.
Example: PRIV_USER="jeffrey"
PROXY_USER
A string representing the proxy user (see Section 4.12, “Proxy Users”). The value is empty if user proxying is not in effect.
Example: PROXY_USER="developer"
SERVER_ID
An unsigned integer representing the server ID. This is the same as the value of the server_id system variable.
Example: SERVER_ID="1"
SQLTEXT
A string representing the text of an SQL statement. The value can be empty. Long values may be truncated. The string, like the audit log file itself, is written using UTF-8 (up to 4 bytes per character), so the value may be the result of conversion. For example, the original statement might have been received from the client as an SJIS string.
Example: SQLTEXT="DELETE FROM t1"
STARTUP_OPTIONS
A string representing the options that were given on the command line or in option files when the MySQL server was started.
Example: STARTUP_OPTIONS="--port=3306 --log_output=FILE"
STATUS
An unsigned integer representing the command status: 0 for success, nonzero if an error occurred. This is the same as the value of the mysql_errno() C API function. See the description for STATUS_CODE for information about how it differs from STATUS.
The audit log does not contain the SQLSTATE value or error message. To see the associations between error codes, SQLSTATE values, and messages, see Server Error Message Reference.
Warnings are not logged.
Example: STATUS="1051"
STATUS_CODE
An unsigned integer representing the command status: 0 for success, 1 if an error occurred.
The STATUS_CODE value differs from the STATUS value: STATUS_CODE is 0 for success and 1 for error, which is compatible with the EZ_collector consumer for Audit Vault. STATUS is the value of the mysql_errno() C API function. This is 0 for success and nonzero for error, and thus is not necessarily 1 for error.
Example: STATUS_CODE="0"
USER
A string representing the user name sent by the client. This may differ from the PRIV_USER value.
VERSION
An unsigned integer representing the version of the audit log file format.
Example: VERSION="1"

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