The COLUMNS table provides information about columns in tables.
mysql> desc INFORMATION_SCHEMA.COLUMNS;
+--------------------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------------+--------------+------+-----+---------+-------+
| TABLE_CATALOG | varchar(512) | YES | | NULL | |
| TABLE_SCHEMA | varchar(64) | NO | | | |
| TABLE_NAME | varchar(64) | NO | | | |
| COLUMN_NAME | varchar(64) | NO | | | |
| ORDINAL_POSITION | bigint(21) | NO | | 0 | |
| COLUMN_DEFAULT | longtext | YES | | NULL | |
| IS_NULLABLE | varchar(3) | NO | | | |
| DATA_TYPE | varchar(64) | NO | | | |
| CHARACTER_MAXIMUM_LENGTH | bigint(21) | YES | | NULL | |
| CHARACTER_OCTET_LENGTH | bigint(21) | YES | | NULL | |
| NUMERIC_PRECISION | bigint(21) | YES | | NULL | |
| NUMERIC_SCALE | bigint(21) | YES | | NULL | |
| CHARACTER_SET_NAME | varchar(64) | YES | | NULL | |
| COLLATION_NAME | varchar(64) | YES | | NULL | |
| COLUMN_TYPE | longtext | NO | | | |
| COLUMN_KEY | varchar(3) | NO | | | |
| EXTRA | varchar(20) | NO | | | |
| PRIVILEGES | varchar(80) | NO | | | |
| COLUMN_COMMENT | varchar(255) | NO | | | |
+--------------------------+--------------+------+-----+---------+-------+
19 rows in set (0.02 sec)
The following statements are nearly equivalent:
SELECT COLUMN_NAME, DATA_TYPE, IS_NULLABLE, COLUMN_DEFAULT
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_name = 'tbl_name'
[AND table_schema = 'db_name']
[AND column_name LIKE 'wild']
SHOW COLUMNS
FROM tbl_name
[FROM db_name]
[LIKE 'wild']