The INNODB_SYS_COLUMNS table provides status
information about InnoDB table columns,
equivalent to the information from the
SYS_COLUMNS table in the
InnoDB data dictionary.
Table 20.9. INNODB_SYS_COLUMNS Columns
| Column name | Description |
|---|---|
TABLE_ID | An identifier representing the table associated with the column; the
same value from
INNODB_SYS_TABLES.TABLE_ID. |
NAME | The name of each column in each table. These names can be uppercase or
lowercase depending on the
lower_case_table_names
setting. There are no special system-reserved names for
columns. |
POS | The ordinal position of the column within the table, starting from 0 and incrementing sequentially. When a column is dropped, the remaining columns are reordered so that the sequence has no gaps. |
MTYPE | A numeric identifier for the column type. 1 =
VARCHAR, 2 = CHAR, 3
= FIXBINARY, 4 =
BINARY, 5 = BLOB, 6
= INT, 7 =
SYS_CHILD, 8 = SYS,
9 = FLOAT, 10 =
DOUBLE, 11 =
DECIMAL, 12 =
VARMYSQL, 13 =
MYSQL. |
PRTYPE | The InnoDB “precise type”, a binary
value with bits representing MySQL data type, character
set code, and nullability. |
LEN | The column length, for example 4 for INT and 8 for
BIGINT. For character columns in
multi-byte character sets, this length value is the
maximum length in bytes needed to represent a definition
such as
VARCHAR(;
that is, it might be
2*,
3*, and so
on depending on the character encoding. |
Notes:
Since the INFORMATION_SCHEMA is a
general-purpose way to monitor the MySQL server, use this
table rather than the corresponding InnoDB
system table for any new monitoring application you develop.
You must have the PROCESS privilege to
query this table.