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# SHOW FUNCTION
## description
### Syntax

```
SHOW FUNCTION [FROM db]
```

### Parameters

> `db`: 要查询的数据库名字


查看数据库下所有的自定义函数。如果用户指定了数据库，那么查看对应数据库的，否则直接查询当前会话所在数据库

需要对这个数据库拥有 `SHOW` 权限

## example

```
mysql> show function in testDb\G
*************************** 1. row ***************************
        Signature: my_count(BIGINT)
      Return Type: BIGINT
    Function Type: Aggregate
Intermediate Type: NULL
       Properties: {"object_file":"http://host:port/libudasample.so","finalize_fn":"_ZN9doris_udf13CountFinalizeEPNS_15FunctionContextERKNS_9BigIntValE","init_fn":"_ZN9doris_udf9CountInitEPNS_15FunctionContextEPNS_9BigIntValE","merge_fn":"_ZN9doris_udf10CountMergeEPNS_15FunctionContextERKNS_9BigIntValEPS2_","md5":"37d185f80f95569e2676da3d5b5b9d2f","update_fn":"_ZN9doris_udf11CountUpdateEPNS_15FunctionContextERKNS_6IntValEPNS_9BigIntValE"}
*************************** 2. row ***************************
        Signature: my_add(INT,INT)
      Return Type: INT
    Function Type: Scalar
Intermediate Type: NULL
       Properties: {"symbol":"_ZN9doris_udf6AddUdfEPNS_15FunctionContextERKNS_6IntValES4_","object_file":"http://host:port/libudfsample.so","md5":"cfe7a362d10f3aaf6c49974ee0f1f878"}
2 rows in set (0.00 sec)
```

## keyword

    SHOW,FUNCTION