| --- |
| title: TRUNCATE |
| --- |
| |
| Empties a table of all rows. |
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| ## <a id="topic1__section2"></a>Synopsis |
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| ``` pre |
| TRUNCATE [TABLE] <name> [, ...] [CASCADE | RESTRICT] |
| ``` |
| |
| ## <a id="topic1__section3"></a>Description |
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| `TRUNCATE` quickly removes all rows from a table or set of tables.This is most useful on large tables. |
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| ## <a id="topic1__section4"></a>Parameters |
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| <dt> \<name\> </dt> |
| <dd>Required. The name (optionally schema-qualified) of a table to be truncated.</dd> |
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| <dt>CASCADE </dt> |
| <dd>Since this key word applies to foreign key references (which are not supported in HAWQ) it has no effect.</dd> |
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| <dt>RESTRICT </dt> |
| <dd>Since this key word applies to foreign key references (which are not supported in HAWQ) it has no effect.</dd> |
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| ## <a id="topic1__section5"></a>Notes |
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| Only the owner of a table may `TRUNCATE` it. `TRUNCATE` will not perform the following: |
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| - Run any user-defined `ON DELETE` triggers that might exist for the tables. |
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| **Note:** HAWQ does not support user-defined triggers. |
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| - Truncate any tables that inherit from the named table. Only the named table is truncated, not its child tables. |
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| ## <a id="topic1__section6"></a>Examples |
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| Empty the table `films`: |
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| ``` sql |
| TRUNCATE films; |
| ``` |
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| ## <a id="topic1__section7"></a>Compatibility |
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| There is no `TRUNCATE` command in the SQL standard. |
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| ## <a id="topic1__section8"></a>See Also |
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| [DROP TABLE](DROP-TABLE.html) |