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---
{
"title": "EXPLODE",
"language": "en"
}
---
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## explode
### description
Table functions must be used in conjunction with Lateral View.
explode array column to rows. `explode_outer` will return NULL, while `array` is NULL or empty.
`explode` and `explode_outer` both keep the nested NULL elements of array.
#### syntax
```sql
explode(expr)
explode_outer(expr)
```
### example
```
mysql> select e1 from (select 1 k1) as t lateral view explode([1,2,3]) tmp1 as e1;
+------+
| e1 |
+------+
| 1 |
| 2 |
| 3 |
+------+
mysql> select e1 from (select 1 k1) as t lateral view explode_outer(null) tmp1 as e1;
+------+
| e1 |
+------+
| NULL |
+------+
mysql> select e1 from (select 1 k1) as t lateral view explode([]) tmp1 as e1;
Empty set (0.010 sec)
mysql> select e1 from (select 1 k1) as t lateral view explode([null,1,null]) tmp1 as e1;
+------+
| e1 |
+------+
| NULL |
| 1 |
| NULL |
+------+
mysql> select e1 from (select 1 k1) as t lateral view explode_outer([null,1,null]) tmp1 as e1;
+------+
| e1 |
+------+
| NULL |
| 1 |
| NULL |
+------+
```
### keywords
EXPLODE,EXPLODE_OUTER,ARRAY