SHOW COLUMNS

The SHOW COLUMNS statement shows details about columns in a table, including each column's name, type, default value, and whether or not it's nullable.

Required privileges

The user must have any privilege on the target table.

Synopsis

SHOWCOLUMNSFROMtable_name

Parameters

ParameterDescription
table_nameThe name of the table for which to show columns.

Response

The following fields are returned for each column.

FieldDescription
column_nameThe name of the column.
data_typeThe data type of the column.
is_nullableWhether or not the column accepts NULL. Possible values: true or false.
column_defaultThe default value for the column, or an expression that evaluates to a default value.
generation_expressionThe expression used for a computed column.
indicesThe list of indexes that the column is involved in, as an array.
is_hiddenWhether or not the column is hidden. Possible values: true or false.

Examples

  1. > CREATE TABLE orders (
  2.     id INT PRIMARY KEY DEFAULT unique_rowid(),
  3.     date TIMESTAMP NOT NULL,
  4.     priority INT DEFAULT 1,
  5.     customer_id INT UNIQUE,
  6.     status STRING DEFAULT 'open',
  7.     CHECK (priority BETWEEN 1 AND 5),
  8.     CHECK (status in ('open', 'in progress', 'done', 'cancelled')),
  9.     FAMILY (id, date, priority, customer_id, status)
  10. );
  1. > SHOW COLUMNS FROM orders;
  1.   column_name | data_type | is_nullable | column_default  | generation_expression |               indices                | is_hidden
  2. +-------------+-----------+-------------+-----------------+-----------------------+--------------------------------------+-----------+
  3.   id          | INT       |    false    | unique_rowid()  |                       | {"primary","orders_customer_id_key"} |   false
  4.   date        | TIMESTAMP |    false    | NULL            |                       | {}                                   |   false
  5.   priority    | INT       |    true     | 1:::INT         |                       | {}                                   |   false
  6.   customer_id | INT       |    true     | NULL            |                       | {"orders_customer_id_key"}           |   false
  7.   status      | STRING    |    true     | 'open':::STRING |                       | {}                                   |   false
  8. (5 rows)
  1. > CREATE TABLE foo (x INT);
  1. > SHOW COLUMNS FROM foo;
  1.   column_name | data_type | is_nullable | column_default | generation_expression |   indices   | is_hidden
  2. +-------------+-----------+-------------+----------------+-----------------------+-------------+-----------+
  3.   x           | INT       |    true     | NULL           |                       | {}          |   false
  4.   rowid       | INT       |    false    | unique_rowid() |                       | {"primary"} |   true
  5. (2 rows)

See also

Was this page helpful?
YesNo