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SingleStoreDB v8.1

DESCRIBE

Describe the specified table.

Syntax

DESCRIBE [<database_name>.]<table_name>;

Remarks

  • <table_name> is the name of a table in a database.

  • <database_name> is the name of a database. Not needed if the table exists in the current database.

  • This command can be run on any node (see Node Requirements for SingleStoreDB Commands ).

  • key has three possible values, primary (PRI), unique (UNI), and multiple (MUL).

    • PRI: A primary key can be one or more columns, but cannot be null.

    • UNI: A unique key is similar to a primary but it can have null values.

    • MUL: A multiple key is neither a primary or unique key.  It can have a null value and multiple occurrences of the same value.

Warning

When setting a unique or primary key you need to have a shard key. Otherwise you will receive an error.

Examples

DESCRIBE test;
****
+-------+-------------+------+-----+---------+----------------+
| Field | Type        | Null | Key | Default | Extra          |
+-------+-------------+------+-----+---------+----------------+
| id    | int(11)     | NO   | PRI | NULL    | auto_increment |
| v     | varchar(10) | NO   |     | NULL    |                |
+-------+-------------+------+-----+---------+----------------+

DESCRIBE memsql_demo.customer;
****
+------------+---------------+------+-----+---------+-------+
| Field      | Type          | Null | Key | Default | Extra |
+------------+---------------+------+-----+---------+-------+
| custkey    | int(11)       | NO   | PRI | NULL    |       |
| name       | varchar(25)   | NO   |     | NULL    |       |
| address    | varchar(40)   | NO   |     | NULL    |       |
| nationkey  | int(11)       | NO   | MUL | NULL    |       |
| phone      | char(15)      | NO   |     | NULL    |       |
| acctbal    | decimal(15,2) | NO   |     | NULL    |       |
| mktsegment | char(10)      | NO   |     | NULL    |       |
| comment    | varchar(117)  | NO   |     | NULL    |       |
| zip2       | binary(5)     | YES  |     | NULL    |       |
| balance    | double        | YES  |     | NULL    |       |
+------------+---------------+------+-----+---------+-------+
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