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---
{
"title": "EXPLODE_MAP",
"language": "en",
"description": "The explodemap table function accepts a map type and expands the map into multiple rows, each containing a key-value pair."
}
---
## Description
The `explode_map` table function accepts a map type and expands the map into multiple rows, each containing a key-value pair.
It should be used together with [`LATERAL VIEW`](../../../query-data/lateral-view.md).
## Syntax
```sql
EXPLODE_MAP(<map>)
```
## Parameters
- `<map>` MAP type.
## Return Value
- Returns a single-column, multi-row result composed of all elements in `<map>`. The column type is `Nullable<Struct<K, V>>`.
- If `<map>` is NULL or empty, 0 rows are returned.
## Examples
0. Prepare data
```sql
create table example(
k1 int
) properties(
"replication_num" = "1"
);
insert into example values(1);
```
1. Regular parameters
```sql
select * from example lateral view explode_map_outer(map("k", "v", "k2", 123, null, null)) t2 as c;
```
```text
+------+-----------------------------+
| k1 | c |
+------+-----------------------------+
| 1 | {"col1":"k", "col2":"v"} |
| 1 | {"col1":"k2", "col2":"123"} |
| 1 | {"col1":null, "col2":null} |
+------+-----------------------------+
```
2. Expand key-value pairs into separate columns
```sql
select * from example lateral view explode_map_outer(map("k", "v", "k2", 123, null, null)) t2 as k, v;
```
```text
+------+------+------+
| k1 | k | v |
+------+------+------+
| 1 | k | v |
| 1 | k2 | 123 |
| 1 | NULL | NULL |
+------+------+------+
```
3. Empty object
```sql
select * from example lateral view explode_map(map()) t2 as c;
```
```text
Empty set (0.03 sec)
```
4. NULL parameter
```sql
select * from example lateral view explode_map(NULL) t2 as c;
```
```text
Empty set (0.03 sec)
```