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

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# PERCENTILE
## description
### Syntax

`PERCENTILE(expr, DOUBLE p)`

计算精确的百分位数，适用于小数据量。先对指定列降序排列，然后取精确的第 p 位百分数。p的值介于0到1之间

参数说明
expr：必填。值为整数（最大为bigint） 类型的列。
p：必填。需要精确的百分位数。取值为 [0.0,1.0]。

## example
```
MySQL > select `table`, percentile(cost_time,0.99) from log_statis group by `table`;
+---------------------+---------------------------+
| table    |        percentile(`cost_time`, 0.99) |
+----------+--------------------------------------+
| test     |                                54.22 |
+----------+--------------------------------------+
```

## keyword
PERCENTILE