---
{
    "title": "coalesce",
    "language": "en"
}
---

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# coalesce
## Description
### Syntax

`VARCHAR coalesce(VARCHAR, ...)`
`...`
`INT coalesce(INT, ...)`

` coalesce ` function will return the first not null value. If it's all value is null, return null

## example

```
MySQL> select coalesce(1,null,2);
+----------------------+
| coalesce(1, NULL, 2) |
+----------------------+
|                    1 |
+----------------------+

MySQL> select coalesce(null,"asd",1);
+--------------------------+
| coalesce(NULL, 'asd', 1) |
+--------------------------+
| asd                      |
+--------------------------+

MySQL> select coalesce(null,null,null);
+----------------------------+
| coalesce(NULL, NULL, NULL) |
+----------------------------+
|                       NULL |
+----------------------------+
```
## keyword
coalesce