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The INFORMATION_SCHEMA COLUMNS Table

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']