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---
{
"title": "explode_json_array",
"language": "en"
}
---
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## `explode_json_array`
### description
Table functions must be used in conjunction with Lateral View.
Expand a json array. According to the array element type, there are three function names. Corresponding to integer, floating point and string arrays respectively.
grammar:
```
explode_json_array_int(json_str)
explode_json_array_double(json_str)
explode_json_array_string(json_str)
```
### example
Original table data:
```
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 |
+------+------+
```
### keywords
explode_json_array