docs/sql-ref-syntax-aux-cache-refresh-function.md

---
layout: global
title: REFRESH FUNCTION
displayTitle: REFRESH FUNCTION
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  this work for additional information regarding copyright ownership.
  The ASF licenses this file to You under the Apache License, Version 2.0
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---

### Description

`REFRESH FUNCTION` statement invalidates the cached function entry, which includes a class name
and resource location of the given function. The invalidated cache is populated right away.
Note that `REFRESH FUNCTION` only works for permanent functions. Refreshing native functions or temporary functions will cause an exception.

### Syntax

```sql
REFRESH FUNCTION function_identifier
```

### Parameters

* **function_identifier**

    Specifies a function name, which is either a qualified or unqualified name. If no database identifier is provided, uses the current database.

    **Syntax:** `[ database_name. ] function_name`

### Examples

```sql
-- The cached entry of the function will be refreshed
-- The function is resolved from the current database as the function name is unqualified.
REFRESH FUNCTION func1;

-- The cached entry of the function will be refreshed
-- The function is resolved from tempDB database as the function name is qualified.
REFRESH FUNCTION db1.func1;   
```

### Related Statements

* [CACHE TABLE](sql-ref-syntax-aux-cache-cache-table.html)
* [CLEAR CACHE](sql-ref-syntax-aux-cache-clear-cache.html)
* [UNCACHE TABLE](sql-ref-syntax-aux-cache-uncache-table.html)
* [REFRESH TABLE](sql-ref-syntax-aux-cache-refresh-table.html)
* [REFRESH](sql-ref-syntax-aux-cache-refresh.html)