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---
{
"title": "EXPLODE_SPLIT",
"language": "en",
"description": "The explodesplit table function is used to split a string into multiple substrings according to the specified delimiter,"
}
---
## Description
The `explode_split` table function is used to split a string into multiple substrings according to the specified delimiter, and expand each substring into a separate row.
It should be used together with [`LATERAL VIEW`](../../../query-data/lateral-view.md) to flatten nested data structures into a standard flat table format.
The main difference between `explode_split` and [`explode_split_outer`](./explode-split-outer.md) is how they handle null values.
## Syntax
```sql
EXPLODE_SPLIT(<str>, <delimiter>)
```
## Parameters
- `<str>` String type, the string to be split.
- `<delimiter>` String type, the delimiter.
## Return Value
- Returns a column composed of the split substrings, with column type String.
## Usage Notes
1. If `<str>` is NULL, 0 rows are returned.
2. If `<str>` is an empty string ("") or cannot be split, 1 row is returned.
3. If `<delimiter>` is NULL, 0 rows are returned.
4. If `<delimiter>` is an empty string (""), `<str>` will be split by bytes([`SPLIT_BY_STRING`](../scalar-functions/string-functions/split-by-string.md)).
## 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_split("ab,cd,ef", ",") t2 as c;
```
```text
+------+------+
| k1 | c |
+------+------+
| 1 | ab |
| 1 | cd |
| 1 | ef |
+------+------+
```
2. Empty string and unsplittable cases
```sql
select * from example lateral view explode_split("", ",") t2 as c;
```
```text
+------+------+
| k1 | c |
+------+------+
| 1 | |
+------+------+
```
```sql
select * from example lateral view explode_split("abc", ",") t2 as c;
```
```text
+------+------+
| k1 | c |
+------+------+
| 1 | abc |
+------+------+
```
3. NULL parameter
```sql
select * from example lateral view explode_split(NULL, ',') t2 as c;
```
```text
Empty set (0.03 sec)
```
4. Empty delimiter
```sql
select * from example lateral view explode_split('abc', '') t2 as c;
```
```text
+------+------+
| k1 | c |
+------+------+
| 1 | a |
| 1 | b |
| 1 | c |
+------+------+
```
5. Delimiter is NULL
```sql
select * from example lateral view explode_split('abc', null) t2 as c;
```
```text
Empty set (0.03 sec)
```