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.. -*- rst -*-
.. highlightlang:: none
``truncate``
============
Summary
-------
``truncate`` command deletes all records from specified table or all
values from specified column.
Syntax
------
This command takes only one required parameter::
truncate target_name
.. versionadded:: 4.0.9
``target_name`` parameter can be used since 4.0.9. You need to use
``table`` parameter for 4.0.8 or earlier.
For backward compatibility, ``truncate`` command accepts ``table``
parameter. But it should not be used for newly written code.
Usage
-----
Here is a simple example of ``truncate`` command against a table.
.. groonga-command
.. database: commands_truncate_table
.. include:: ../../example/reference/commands/truncate/truncate_table.log
.. table_create Users TABLE_PAT_KEY ShortText
.. column_create Users score COLUMN_SCALAR Int32
.. load --table Users
.. [
.. {"_key": "Alice", "score": 2},
.. {"_key": "Bob", "score": 0},
.. {"_key": "Carlos", "score": -1}
.. ]
.. select Users
.. truncate Users
.. select Users
Here is a simple example of ``truncate`` command against a column.
.. groonga-command
.. database: commands_truncate_column
.. include:: ../../example/reference/commands/truncate/truncate_column.log
.. table_create Users TABLE_PAT_KEY ShortText
.. column_create Users score COLUMN_SCALAR Int32
.. load --table Users
.. [
.. {"_key": "Alice", "score": 2},
.. {"_key": "Bob", "score": 0},
.. {"_key": "Carlos", "score": -1}
.. ]
.. select Users
.. truncate Users.score
.. select Users
Parameters
----------
This section describes parameters of ``truncate``.
Required parameters
^^^^^^^^^^^^^^^^^^^
There is required parameter, ``target_name``.
``target_name``
"""""""""""""""
Specifies the name of table or column.
Return value
------------
``truncate`` command returns whether truncation is succeeded or not::
[HEADER, SUCCEEDED_OR_NOT]
``HEADER``
See :doc:`/reference/command/output_format` about ``HEADER``.
``SUCCEEDED_OR_NOT``
If command succeeded, it returns true, otherwise it returns false on error.
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