示例 SHOW functions; --使用LIKE子句show functions like 'boo_%'; Function | Return Type | Argument Types | Function Type | Deterministic | Description ----------|-------------|----------------|---------------|---------------|------------- bool_and | boolean | boolean | aggregate | true | bool_or | boolean | boolean | aggregate | true | (2 rows)--如果匹配字符串中有字符与通配符冲突，可以指定转义字符来标识，示例为查询default这个schema下，table_name前缀为＂t_＂ 的所有table，转义字符为＂\＂:SHOW FUNCTIONS LIKE 'array\_%' escape '\'; Function | Return Type | Argument Types | Function Type | Deterministic | Description | Variable Arity | Built In -----------------|-------------|---------------------------------|---------------|---------------|--------------------------------------------------------------------------------------------------------|----------------|---------- array_agg | array(T) | T | aggregate | true | return an array of values | false | true array_contains | boolean | array(T), T | scalar | true | Determines whether given value exists in the array | false | true array_distinct | array(E) | array(E) | scalar | true | Remove duplicate values from the given array | false | true array_except | array(E) | array(E), array(E) | scalar | true | Returns an array of elements that are in the first array but not the second, without duplicates. | false | true array_intersect | array(E) | array(E), array(E) | scalar | true | Intersects elements of the two given arrays | false | true array_join | varchar | array(T), varchar | scalar | true | Concatenates the elements of the given array using a delimiter and an optional string to replace nulls | false | true array_join | varchar | array(T), varchar, varchar | scalar | true | Concatenates the elements of the given array using a delimiter and an optional string to replace nulls | false | true array_max | T | array(T) | scalar | true | Get maximum value of array | false | true array_min | T | array(T) | scalar | true | Get minimum value of array | false | true array_position | bigint | array(T), T | scalar | true | Returns the position of the first occurrence of the given value in array (or 0 if not found) | false | true array_remove | array(E) | array(E), E | scalar | true | Remove specified values from the given array | false | true array_sort | array(E) | array(E) | scalar | true | Sorts the given array in ascending order according to the natural ordering of its elements. | false | true array_sort | array(T) | array(T), function(T,T,integer) | scalar | true | Sorts the given array with a lambda comparator. | false | true array_union | array(E) | array(E), array(E) | scalar | true | Union elements of the two given arrays | false | true --查看所有JAVA函数SHOW external functions; Function | Owner ----------------------------|----------- example.namespace02.repeat | admintest hetu.default.add_two | admintest (2 rows)--查看给定函数的定义信息SHOW external function example.namespace02.repeat; External Function --------------------------------------External FUNCTION example.namespace02.repeat ( s varchar, n integer ) RETURNS varchar COMMENT 'repeat' LANGUAGE JAVA DETERMINISTIC CALLED ON NULL INPUT SYMBOL com.test.udf.hetuengine.functions.repeat URI hdfs://hacluster/user/hetuserver/udf/data/hetu_udf/udf-test-0.0.1-SNAPSHOT.jar FUNCPROPERTIES ( owner = 'admintest' )