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

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## bit_length
### description
#### Syntax

`INT bit_length(VARCHAR str)`


返回字符串的位长度。

### example

```
mysql> select bit_length("abc");
+-------------------+
| bit_length('abc') |
+-------------------+
|                24 |
+-------------------+

mysql> select bit_length("中国");
+----------------------+
| bit_length('中国')    |
+----------------------+
|                   48 |
+----------------------+
```
### keywords
BIT_LENGTH