explode_json_array

description

表函数，需配合 Lateral View 使用。

展开一个 json 数组。根据数组元素类型，有三种函数名称。分别对应整型、浮点和字符串数组。

语法：

explode_json_array_int(json_str)
explode_json_array_double(json_str)
explode_json_array_string(json_str)

example

原表数据：

mysql> select k1 from example1 order by k1;
+------+
| k1   |
+------+
|    1 |
|    2 |
|    3 |
|    4 |
|    5 |
|    6 |
+------+

Lateral View:

mysql> select k1, e1 from example1 lateral view explode_json_array_int('[]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    2 | NULL |
|    3 | NULL |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_int('[1,2,3]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 |    1 |
|    1 |    2 |
|    1 |    3 |
|    2 |    1 |
|    2 |    2 |
|    2 |    3 |
|    3 |    1 |
|    3 |    2 |
|    3 |    3 |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_int('[1,"b",3]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    1 |    1 |
|    1 |    3 |
|    2 | NULL |
|    2 |    1 |
|    2 |    3 |
|    3 | NULL |
|    3 |    1 |
|    3 |    3 |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_int('["a","b","c"]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    1 | NULL |
|    1 | NULL |
|    2 | NULL |
|    2 | NULL |
|    2 | NULL |
|    3 | NULL |
|    3 | NULL |
|    3 | NULL |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_int('{"a": 3}') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    2 | NULL |
|    3 | NULL |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_double('[]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    2 | NULL |
|    3 | NULL |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_double('[1,2,3]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    1 | NULL |
|    1 | NULL |
|    2 | NULL |
|    2 | NULL |
|    2 | NULL |
|    3 | NULL |
|    3 | NULL |
|    3 | NULL |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_double('[1,"b",3]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    1 | NULL |
|    1 | NULL |
|    2 | NULL |
|    2 | NULL |
|    2 | NULL |
|    3 | NULL |
|    3 | NULL |
|    3 | NULL |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_double('[1.0,2.0,3.0]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 |    1 |
|    1 |    2 |
|    1 |    3 |
|    2 |    1 |
|    2 |    2 |
|    2 |    3 |
|    3 |    1 |
|    3 |    2 |
|    3 |    3 |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_double('[1,"b",3]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    1 | NULL |
|    1 | NULL |
|    2 | NULL |
|    2 | NULL |
|    2 | NULL |
|    3 | NULL |
|    3 | NULL |
|    3 | NULL |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_double('["a","b","c"]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    1 | NULL |
|    1 | NULL |
|    2 | NULL |
|    2 | NULL |
|    2 | NULL |
|    3 | NULL |
|    3 | NULL |
|    3 | NULL |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_double('{"a": 3}') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    2 | NULL |
|    3 | NULL |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_string('[]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    2 | NULL |
|    3 | NULL |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_string('[1.0,2.0,3.0]') tmp1 as e1 order by k1, e1;
+------+----------+
| k1   | e1       |
+------+----------+
|    1 | 1.000000 |
|    1 | 2.000000 |
|    1 | 3.000000 |
|    2 | 1.000000 |
|    2 | 2.000000 |
|    2 | 3.000000 |
|    3 | 1.000000 |
|    3 | 2.000000 |
|    3 | 3.000000 |
+------+----------+
mysql> select k1, e1 from example1 lateral view explode_json_array_string('[1,"b",3]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | 1    |
|    1 | 3    |
|    1 | b    |
|    2 | 1    |
|    2 | 3    |
|    2 | b    |
|    3 | 1    |
|    3 | 3    |
|    3 | b    |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_string('["a","b","c"]') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | a    |
|    1 | b    |
|    1 | c    |
|    2 | a    |
|    2 | b    |
|    2 | c    |
|    3 | a    |
|    3 | b    |
|    3 | c    |
+------+------+
mysql> select k1, e1 from example1 lateral view explode_json_array_string('{"a": 3}') tmp1 as e1 order by k1, e1;
+------+------+
| k1   | e1   |
+------+------+
|    1 | NULL |
|    2 | NULL |
|    3 | NULL |
+------+------+

keyword

explode_json_array