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SHOW [FULL] COLUMNS FROM
TiDB 数据库中 SHOW [FULL] COLUMNS FROM 的使用概况。
/docs-cn/dev/sql-statements/sql-statement-show-columns-from/
/docs-cn/dev/reference/sql/statements/show-columns-from/

SHOW [FULL] COLUMNS FROM

SHOW [FULL] COLUMNS FROM <table_name> 语句用于以表格格式描述表或视图中的列。可选关键字 FULL 用于显示当前用户对该列的权限，以及表定义中的 comment。

SHOW [FULL] FIELDS FROM <table_name>、DESC <table_name>、DESCRIBE <table_name> 和 EXPLAIN <table_name> 语句都是 SHOW [FULL] COLUMNS FROM 的别名。

注意：

DESC TABLE <table_name>、DESCRIBE TABLE <table_name> 和 EXPLAIN TABLE <table_name> 与上面的语句并不等价，它们是 DESC SELECT * FROM <table_name> 的别名。

语法图

ShowStmt:

ShowStmt

ShowColumnsFilterable:

ShowColumnsFilterable

OptFull:

OptFull

FieldsOrColumns:

FieldsOrColumns

ShowTableAliasOpt:

ShowTableAliasOpt

FromOrIn:

FromOrIn

TableName:

TableName

ShowDatabaseNameOpt:

ShowDatabaseNameOpt

DBName:

DBName

ShowLikeOrWhereOpt:

ShowLikeOrWhereOpt

示例

{{< copyable "sql" >}}

create view v1 as select 1;
Query OK, 0 rows affected (0.11 sec)

{{< copyable "sql" >}}

show columns from v1;
+-------+-----------+------+------+---------+-------+
| Field | Type      | Null | Key  | Default | Extra |
+-------+-----------+------+------+---------+-------+
| 1     | bigint(1) | YES  |      | NULL    |       |
+-------+-----------+------+------+---------+-------+
1 row in set (0.00 sec)

{{< copyable "sql" >}}

desc v1;
+-------+-----------+------+------+---------+-------+
| Field | Type      | Null | Key  | Default | Extra |
+-------+-----------+------+------+---------+-------+
| 1     | bigint(1) | YES  |      | NULL    |       |
+-------+-----------+------+------+---------+-------+
1 row in set (0.00 sec)

{{< copyable "sql" >}}

describe v1;
+-------+-----------+------+------+---------+-------+
| Field | Type      | Null | Key  | Default | Extra |
+-------+-----------+------+------+---------+-------+
| 1     | bigint(1) | YES  |      | NULL    |       |
+-------+-----------+------+------+---------+-------+
1 row in set (0.00 sec)

{{< copyable "sql" >}}

explain v1;
+-------+-----------+------+------+---------+-------+
| Field | Type      | Null | Key  | Default | Extra |
+-------+-----------+------+------+---------+-------+
| 1     | bigint(1) | YES  |      | NULL    |       |
+-------+-----------+------+------+---------+-------+
1 row in set (0.00 sec)

{{< copyable "sql" >}}

show fields from v1;
+-------+-----------+------+------+---------+-------+
| Field | Type      | Null | Key  | Default | Extra |
+-------+-----------+------+------+---------+-------+
| 1     | bigint(1) | YES  |      | NULL    |       |
+-------+-----------+------+------+---------+-------+
1 row in set (0.00 sec)

{{< copyable "sql" >}}

show full columns from v1;
+-------+-----------+-----------+------+------+---------+-------+---------------------------------+---------+
| Field | Type      | Collation | Null | Key  | Default | Extra | Privileges                      | Comment |
+-------+-----------+-----------+------+------+---------+-------+---------------------------------+---------+
| 1     | bigint(1) | NULL      | YES  |      | NULL    |       | select,insert,update,references |         |
+-------+-----------+-----------+------+------+---------+-------+---------------------------------+---------+
1 row in set (0.00 sec)

{{< copyable "sql" >}}

show full columns from mysql.user;
+-----------------------+---------------+-------------+------+------+---------+-------+---------------------------------+---------+
| Field                 | Type          | Collation   | Null | Key  | Default | Extra | Privileges                      | Comment |
+-----------------------+---------------+-------------+------+------+---------+-------+---------------------------------+---------+
| Host                  | char(64)      | utf8mb4_bin | NO   | PRI  | NULL    |       | select,insert,update,references |         |
| User                  | char(32)      | utf8mb4_bin | NO   | PRI  | NULL    |       | select,insert,update,references |         |
| authentication_string | text          | utf8mb4_bin | YES  |      | NULL    |       | select,insert,update,references |         |
| Select_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Insert_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Update_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Delete_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Create_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Drop_priv             | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Process_priv          | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Grant_priv            | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| References_priv       | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Alter_priv            | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Show_db_priv          | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Super_priv            | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Create_tmp_table_priv | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Lock_tables_priv      | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Execute_priv          | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Create_view_priv      | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Show_view_priv        | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Create_routine_priv   | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Alter_routine_priv    | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Index_priv            | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Create_user_priv      | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Event_priv            | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Trigger_priv          | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Create_role_priv      | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Drop_role_priv        | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Account_locked        | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Shutdown_priv         | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Reload_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| FILE_priv             | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
| Config_priv           | enum('N','Y') | utf8mb4_bin | NO   |      | N       |       | select,insert,update,references |         |
+-----------------------+---------------+-------------+------+------+---------+-------+---------------------------------+---------+
33 rows in set (0.01 sec)

MySQL 兼容性

SHOW [FULL] COLUMNS FROM 语句与 MySQL 完全兼容。如发现任何兼容性差异，请在 GitHub 上提交 issue。

另请参阅