---
{
    "title": "coalesce",
    "language": "zh-CN"
}
---

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# coalesce
## description
### Syntax

`coalesce(expr1, expr2, ...., expr_n))`

返回参数中的第一个非空表达式（从左向右）

## example

```
mysql> select coalesce(NULL, '1111', '0000');
+--------------------------------+
| coalesce(NULL, '1111', '0000') |
+--------------------------------+
| 1111                           |
+--------------------------------+
```
## keyword

    COALESCE