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  • sql server 生成数字辅助表

      这里使用2的次幂,用的公用表表达式生成

    IF OBJECT_ID('dbo.GetNums') IS NOT NULL
      DROP FUNCTION dbo.GetNums;
    GO
    CREATE FUNCTION dbo.GetNums(@n AS BIGINT) RETURNS TABLE
    AS
    RETURN
      WITH
      L0   AS(SELECT 1 AS c UNION ALL SELECT 1),
      L1   AS(SELECT 1 AS c FROM L0 AS A CROSS JOIN L0 AS B),
      L2   AS(SELECT 1 AS c FROM L1 AS A CROSS JOIN L1 AS B),
      L3   AS(SELECT 1 AS c FROM L2 AS A CROSS JOIN L2 AS B),
      L4   AS(SELECT 1 AS c FROM L3 AS A CROSS JOIN L3 AS B),
      L5   AS(SELECT 1 AS c FROM L4 AS A CROSS JOIN L4 AS B),
      Nums AS(SELECT ROW_NUMBER() OVER(ORDER BY (SELECT 0)) AS n FROM L5)
      SELECT n FROM Nums WHERE n <= @n;
    GO
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  • 原文地址:https://www.cnblogs.com/student-note/p/12672626.html
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