---
{
    "title": "SHOW-FUNCTIONS",
    "language": "en"
}
---

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## SHOW-FUNCTIONS

### Name

SHOW FUNCTIONS

### Description

View all custom (system-provided) functions under the database. If the user specifies a database, then view the corresponding database, otherwise directly query the database where the current session is located

Requires `SHOW` permission on this database

grammar

```sql
SHOW [FULL] [BUILTIN] FUNCTIONS [IN|FROM db] [LIKE 'function_pattern']
````

 Parameters

>`full`: Indicates the detailed information of the display function
>`builtin`: Indicates the functions provided by the display system
>`db`: database name to query
>`function_pattern`: parameter used to filter function names

### Example

````sql
mysql> show full functions in testDb\G
**************************** 1. 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. 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"}
**************************** 3. row ******************** ******
        Signature: id_masking(BIGINT)
      Return Type: VARCHAR
    Function Type: Alias
Intermediate Type: NULL
       Properties: {"parameter":"id","origin_function":"concat(left(`id`, 3), `****`, right(`id`, 4))"}

3 rows in set (0.00 sec)
mysql> show builtin functions in testDb like 'year%';
+---------------+
| Function Name |
+---------------+
| year          |
| years_add     |
| years_diff    |
| years_sub     |
+---------------+
2 rows in set (0.00 sec)
````

### Keywords

    SHOW, FUNCTIONS

### Best Practice