Bug #25368 enlarge table comment

• Submitted: 2 Jan 2007 16:01
• Modified: 30 Sep 2008 15:55
• Reporter: Hans Ginzel
• Status: Closed
• Category: MySQL Server
• Severity: S4 (Feature request)
• Version: 5.0.26-community-nt
• OS: Windows (Windows XP)
• CPU Architecture: Any
• Tags: table comment

[2 Jan 2007 16:01] Hans Ginzel

Description:
Please, enlarge table comment to 255 characters.

How to repeat:
desc information_schema.TABLES;
desc information_schema.COLUMNS;

Suggested fix:
alter table information_schema.TABLES
modify TABLE_COMMENT varchar(255);

:-)

[28 Feb 2007 17:53] Valeriy Kravchuk

Thank you for a reasonable feature request. Oracle, for example, allows comments up to 4000 (their varchar2 maximum size) characters long.

[30 Sep 2008 15:55] Konstantin Osipov

mysql> desc information_schema.tables;
+-----------------+---------------------+------+-----+---------+-------+
| Field           | Type                | Null | Key | Default | Extra |
+-----------------+---------------------+------+-----+---------+-------+
| TABLE_CATALOG   | varchar(512)        | YES  |     | NULL    |       | 
| TABLE_SCHEMA    | varchar(64)         | NO   |     |         |       | 
| TABLE_NAME      | varchar(64)         | NO   |     |         |       | 
| TABLE_TYPE      | varchar(64)         | NO   |     |         |       | 
| ENGINE          | varchar(64)         | YES  |     | NULL    |       | 
| VERSION         | bigint(21) unsigned | YES  |     | NULL    |       | 
| ROW_FORMAT      | varchar(10)         | YES  |     | NULL    |       | 
| TABLE_ROWS      | bigint(21) unsigned | YES  |     | NULL    |       | 
| AVG_ROW_LENGTH  | bigint(21) unsigned | YES  |     | NULL    |       | 
| DATA_LENGTH     | bigint(21) unsigned | YES  |     | NULL    |       | 
| MAX_DATA_LENGTH | bigint(21) unsigned | YES  |     | NULL    |       | 
| INDEX_LENGTH    | bigint(21) unsigned | YES  |     | NULL    |       | 
| DATA_FREE       | bigint(21) unsigned | YES  |     | NULL    |       | 
| AUTO_INCREMENT  | bigint(21) unsigned | YES  |     | NULL    |       | 
| CREATE_TIME     | datetime            | YES  |     | NULL    |       | 
| UPDATE_TIME     | datetime            | YES  |     | NULL    |       | 
| CHECK_TIME      | datetime            | YES  |     | NULL    |       | 
| TABLE_COLLATION | varchar(64)         | YES  |     | NULL    |       | 
| CHECKSUM        | bigint(21) unsigned | YES  |     | NULL    |       | 
| CREATE_OPTIONS  | varchar(255)        | YES  |     | NULL    |       | 
| TABLE_COMMENT   | varchar(2048)       | NO   |     |         |       | 
+-----------------+---------------------+------+-----+---------+-------+
21 rows in set (0.00 sec)

mysql> desc information_schema.columns\G
*************************** 1. row ***************************
  Field: TABLE_CATALOG
   Type: varchar(512)
   Null: YES
    Key: 
Default: NULL
  Extra: 
*************************** 2. row ***************************
  Field: TABLE_SCHEMA
   Type: varchar(64)
   Null: NO
    Key: 
Default: 
  Extra: 
*************************** 3. row ***************************
  Field: TABLE_NAME
   Type: varchar(64)
   Null: NO
    Key: 
Default: 
  Extra: 
*************************** 4. row ***************************
  Field: COLUMN_NAME
   Type: varchar(64)
   Null: NO
    Key: 
Default: 
  Extra: 
*************************** 5. row ***************************
  Field: ORDINAL_POSITION
   Type: bigint(21) unsigned
   Null: NO
    Key: 
Default: 0
  Extra: 
*************************** 6. row ***************************
  Field: COLUMN_DEFAULT
   Type: longtext
   Null: YES
    Key: 
Default: NULL
  Extra: 
*************************** 7. row ***************************
  Field: IS_NULLABLE
   Type: varchar(3)
   Null: NO
    Key: 
Default: 
  Extra: 
*************************** 8. row ***************************
  Field: DATA_TYPE
   Type: varchar(64)
   Null: NO
    Key: 
Default: 
  Extra: 
*************************** 9. row ***************************
  Field: CHARACTER_MAXIMUM_LENGTH
   Type: bigint(21) unsigned
   Null: YES
    Key: 
Default: NULL
  Extra: 
*************************** 10. row ***************************
  Field: CHARACTER_OCTET_LENGTH
   Type: bigint(21) unsigned
   Null: YES
    Key: 
Default: NULL
  Extra: 
*************************** 11. row ***************************
  Field: NUMERIC_PRECISION
   Type: bigint(21) unsigned
   Null: YES
    Key: 
Default: NULL
  Extra: 
*************************** 12. row ***************************
  Field: NUMERIC_SCALE
   Type: bigint(21) unsigned
   Null: YES
    Key: 
Default: NULL
  Extra: 
*************************** 13. row ***************************
  Field: CHARACTER_SET_NAME
   Type: varchar(64)
   Null: YES
    Key: 
Default: NULL
  Extra: 
*************************** 14. row ***************************
  Field: COLLATION_NAME
   Type: varchar(64)
   Null: YES
    Key: 
Default: NULL
  Extra: 
*************************** 15. row ***************************
  Field: COLUMN_TYPE
   Type: longtext
   Null: NO
    Key: 
Default: NULL
  Extra: 
*************************** 16. row ***************************
  Field: COLUMN_KEY
   Type: varchar(3)
   Null: NO
    Key: 
Default: 
  Extra: 
*************************** 17. row ***************************
  Field: EXTRA
   Type: varchar(27)
   Null: NO
    Key: 
Default: 
  Extra: 
*************************** 18. row ***************************
  Field: PRIVILEGES
   Type: varchar(80)
   Null: NO
    Key: 
Default: 
  Extra: 
*************************** 19. row ***************************
  Field: COLUMN_COMMENT
   Type: varchar(1024)
   Null: NO
    Key: 
Default: 
  Extra: 
*************************** 20. row ***************************
  Field: STORAGE
   Type: varchar(8)
   Null: NO
    Key: 
Default: 
  Extra: 
*************************** 21. row ***************************
  Field: FORMAT
   Type: varchar(8)
   Null: NO
    Key: 
Default: 
  Extra: 
21 rows in set (0.01 sec)

mysql> select version();
+--------------------------------+
| version()                      |
+--------------------------------+
| 6.0.8-alpha-valgrind-max-debug | 
+--------------------------------+
1 row in set (0.00 sec)

This has been fixed, at least in 6.0.