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oracle12c新特性 去重统计函数APPROX_COUNT_DISTINCT

发表于:2025-02-11 作者:千家信息网编辑
千家信息网最后更新 2025年02月11日,Note:The APPROX_COUNT_DISTINCT function is available starting with Oracle Database 12c Release 1 (12
千家信息网最后更新 2025年02月11日oracle12c新特性 去重统计函数APPROX_COUNT_DISTINCT

Note:

The APPROX_COUNT_DISTINCT function is available starting with Oracle Database 12c Release 1 (12.1.0.2).


用例:

求scott.emp表中一共有多少个部门

11g:SELECT COUNT(DISTINCT deptno) AS cnt FROM scott.emp12c:SELECT APPROX_COUNT_DISTINCT(deptno) AS cnt FROM scott.emp




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