TABLE_MAP_EVENT
Used for row-based binary logging beginning (binlog_format=ROW or MIXED)
This event precedes each row operation event and maps a table definition to a number, where the table definition consists of database and table names.
Header
- Event Type is 19 (0x13)
Fields
Fixed data part:
Variable data part:
- uint<1> Database name length.
- string<NUL> The database name (null-terminated).
- uint<1> Table name length.
- string<NUL> The table name (null-terminated).
- int<lenenc> The number of columns in the table.
- byte<n> An array of 'n' column types, one byte per column.
- int<lenenc> The length of the metadata block.
- byte<n> The metadata block;
- byte<n> Bit-field indicating whether each column can be NULL, one bit per column.
- if (more_data_available)
- byte<n> Optional metadata block;
Metadata block
The metadata block contains type specific metadata information for each column
| Type | Length | Description |
| MYSQL_TYPE_BLOB | 1 | Number of bytes for length: e.g. 4 bytes means length is stored in a 4 byte integer) |
| MYSQL_TYPE_DATETIME2 | 1 | Length of microseconds |
| MYSQL_TYPE_DECIMAL | 2 | Not in use anymore |
| MYSQL_TYPE_DOUBLE ,MYSQL_TYPE_FLOAT | 1 | length (4 or 8 bytes |
| MYSQL_TYPE_STRING | 2 | 1st byte contains type (MYSQL_TYPE_STRING, MYSQL_TYPE_ENUM, or MYSQL_TYPE_SET, 2nd byte contains length |
| MYSQL_TYPE_NEWDECIMAL | 2 | Precision, Scale |
| MYSQL_TYPE_TIME2 | 1 | Length of microseconds |
| MYSQL_TYPE_TIMESTAMP2 | 1 | Length of microseconds |
| MYSQL_TYPE_VARCHAR, MYSQL_TYPE_VAR_STRING | 2 | Defined varchar length. If the value is > 255, length is stored in 2 bytes, otherwise 1 byte |
Optional metadata block
Optional metadata will be available if global server variable BINLOG_ROW_METADATA was set to values MIN or FULL.
The metadata block consists of one or more of the following blocks:
- byte<1> Optional metadata type
- int<lenenc> Length
- byte<length> Data
Optional metadata types:
| Name | Value | Mode | Description |
| SIGNEDNESS | 1 | MIN | Data contains a bitmap indicating which integer columns are signed |
| DEFAULT_CHARSET | 2 | MIN | Character set of string columns, used if most columns have the same result. Columns with other character sets will follow as pair (column_index, collation number). |
| COLUMN_CHARSET | 3 | MIN | Character set of columns, used if columns have different character sets. Returned as a sequence of collation numbers. |
| COLUMN_NAME | 4 | FULL | List of Column names, the first byte specifies the length of the column name |
| SET_STR_VALUE | 5 | FULL | List of set values: First byte is the number of different values, followed by length/value pairs. |
| ENUM_STR_VALUE | 6 | FULL | Same as SET_STR_VALUE. Since ENUM values might have up to 0xFFFF members, the number of values is a length encoded integer. |
| GEOMETRY_TYPE | 7 | FULL | A sequence of bytes repesenting the type of GEOMETRY columns: 0 = GEOMETRY, 1 = POINT, 2 = LINESTRING, 3 = POLYGON, 4=MULTIPOINT, 5 = MULTILINESTRING, 6 = MULTIPOLYGON, 7 = GEOMETRYCOLLECTION |
| SIMPLE_PRIMARY_KEY | 8 | FULL | A sequence of length encoded column indexes. |
| PRIMARY_KEY_WITH_PREFIX | 9 | FULL | A sequence of length encoded column indexes and prefix lengths. |
| ENUM_AND_SET_DEFAULT_CHARSET | 10 | FULL | The default character set number used for ENUM and SET columns |
| ENUM_AND_SET_COLUMN_CHARSET | 11 | FULL | Character set of ENUM and SET columns, used if these columns have different character sets. Returned as a sequence of collation numbers. |
Example From mysqlbinlog
# at 847 #171206 13:43:00 server id 10124 end_log_pos 892 CRC32 0xbe3c6b05 Table_map: `test`.`t4` mapped to number 33 # at 892
Complete Event
d4 e5 27 5a 13 8c 27 00 00 2d 00 00 00 7c 03 00 ..'Z..'..-...|.. 00 00 00 21 00 00 00 00 00 01 00 04 74 65 73 74 ...!........test 00 02 74 34 00 01 03 01 01 05 6b 3c be ..t4......k<.
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