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# SHOW FUNCTION
## Description
### Syntax

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

### Parameters

>` DB `: The name of the database to query


Look at all the custom functions under the database. If the user specifies the database, then look at the corresponding database, otherwise directly query the database where the current session is located.

You need `SHOW'privileges for this database

## 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