DESCRIBE OUTPUT

Synopsis

1. DESCRIBE OUTPUT statement_name

Description

List the output columns of a prepared statement, including the column name (or alias), catalog, schema, table, type, type size in bytes, and a boolean indicating if the column is aliased.

Examples

Prepare and describe a query with four output columns:

1. PREPARE my_select1 FROM
2. SELECT * FROM nation

1. DESCRIBE OUTPUT my_select1;

1. Column Name | Catalog | Schema | Table  |  Type   | Type Size | Aliased
2. -------------+---------+--------+--------+---------+-----------+---------
3. nationkey   | tpch    | sf1    | nation | bigint  |         8 | false
4. name        | tpch    | sf1    | nation | varchar |         0 | false
5. regionkey   | tpch    | sf1    | nation | bigint  |         8 | false
6. comment     | tpch    | sf1    | nation | varchar |         0 | false
7. (4 rows)

Prepare and describe a query whose output columns are expressions:

1. PREPARE my_select2 FROM
2. SELECT count(*) as my_count, 1+2 FROM nation

1. DESCRIBE OUTPUT my_select2;

1. Column Name | Catalog | Schema | Table |  Type  | Type Size | Aliased
2. -------------+---------+--------+-------+--------+-----------+---------
3. my_count    |         |        |       | bigint |         8 | true
4. _col1       |         |        |       | bigint |         8 | false
5. (2 rows)

Prepare and describe a row count query:

1. PREPARE my_create FROM
2. CREATE TABLE foo AS SELECT * FROM nation

1. DESCRIBE OUTPUT my_create;

1. Column Name | Catalog | Schema | Table |  Type  | Type Size | Aliased
2. -------------+---------+--------+-------+--------+-----------+---------
3. rows        |         |        |       | bigint |         8 | false
4. (1 row)

See Also

PREPARE