Path: blob/main/py-polars/docs/source/reference/sql/table_operations.rst
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Table Operations
================
.. list-table::
:header-rows: 1
:widths: 20 60
* - Function
- Description
* - :ref:`CREATE TABLE <create_table>`
- Create a new table and its columns from a SQL query executed against an existing table.
* - :ref:`DELETE FROM <delete_from_table>`
- Remove specific rows of data from a table using an (optional) constraint.
* - :ref:`DROP TABLES <drop_tables>`
- Deletes the specified table, unregistering it.
* - :ref:`EXPLAIN <explain>`
- Returns the Polars execution plan for a given SQL query.
* - :ref:`SHOW TABLES <show_tables>`
- Returns a list of all tables registered in the given context.
* - :ref:`UNNEST <unnest_table_func>`
- Unnest one or more arrays as columns in a new table object.
* - :ref:`TRUNCATE <truncate>`
- Remove all data from a table without actually deleting it.
.. _create_table:
CREATE TABLE
------------
Create a new table and its columns from a SQL query executed against an existing table.
**Example:**
.. code-block:: sql
CREATE TABLE new_table AS
SELECT * FROM existing_table WHERE value > 42
.. _delete_from_table:
DELETE
------
Remove specific rows from a table using an (optional) constraint.
Omitting the constraint deletes all rows, equivalent to TRUNCATE.
**Example:**
.. code-block:: sql
DELETE FROM some_table WHERE value < 0
.. _drop_tables:
DROP TABLES
-----------
Deletes the specified table, unregistering it.
**Example:**
.. code-block:: sql
DROP TABLE old_table
.. _explain:
EXPLAIN
-------
Returns the Polars execution plan for a given SQL query.
**Example:**
.. code-block:: sql
EXPLAIN SELECT * FROM some_table
.. _show_tables:
SHOW TABLES
-----------
Returns a list of all tables registered in the given context.
**Example:**
.. code-block:: sql
SHOW TABLES
.. _unnest_table_func:
UNNEST
------
Unnest one or more arrays as columns in a new table object.
**Example:**
.. code-block:: sql
SELECT * FROM
UNNEST(
[1, 2, 3, 4],
['ww','xx','yy','zz'],
[23.0, 24.5, 28.0, 27.5]
) AS tbl (x,y,z)
.. _truncate:
TRUNCATE
--------
Remove all data from a table without actually deleting it.
**Example:**
.. code-block:: sql
TRUNCATE TABLE some_table