Question

description

Syntax

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

Parameters

full:表示显示函数的详细信息 builtin:表示显示系统提供的函数 db: 要查询的数据库名字 function_pattern: 用来过滤函数名称的参数

查看数据库下所有的自定义(系统提供)的函数。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 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(INT)
      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)

keyword

SHOW,FUNCTIONS