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版本发布记录

approx_count_distinct_precision

更新时间：2026-08-13 19:27:48

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功能描述

approx_count_distinct_precision 用于配置 approx_count_distinct 函数的结果精度。

权限要求

查询配置项

sys 租户和所有用户租户均可以使用 SHOW PARAMETERS 语句或视图 GV$OB_PARAMETERS 查询该配置项。
修改配置项

sys 租户和用户租户均可修改该配置项。

属性说明

属性	描述
参数类型	Integer
默认值	10
取值范围	[4，16]
是否可修改	是，支持通过 `ALTER SYSTEM SET` 语句修改。
是否重启 OBServer 节点生效	否

配置示例

执行如下命令，设置基数估算函数的计算精度为 10。

obclient> ALTER SYSTEM SET approx_count_distinct_precision = 10;

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approx_count_distinct

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approx_count_distinct_precision - OceanBase Database AI V4.6.2 | OceanBase 文档中心