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  • MySQL学习笔记:生成时间维度表2

      实现目的:

      

      测试:

    # 测试 加一秒
    SELECT DATE_SUB(DATE_ADD(CURRENT_DATE(), INTERVAL 1 SECOND), INTERVAL 1 SECOND);
    SELECT DATE_FORMAT(DATE_ADD(CURRENT_DATE(), INTERVAL 1 SECOND),'%H%i%s');# 第一秒
    SELECT DATE_FORMAT(DATE_SUB(CURRENT_DATE(), INTERVAL 1 SECOND),'%H%i%s');# 最后一秒
    SELECT CURRENT_TIME();

      完整代码:

    # ------------ 完整代码 ----------
    SET @d0 = DATE_SUB(DATE_ADD(CURRENT_DATE(), INTERVAL 1 SECOND), INTERVAL 1 SECOND); # 第一秒
    SET @d1 = DATE_ADD(DATE_SUB(DATE_ADD(CURRENT_DATE(), INTERVAL 1 DAY), INTERVAL 1 SECOND),
        INTERVAL 1 SECOND);# 最后一秒
    SET @time = DATE_SUB(@d0, INTERVAL 1 SECOND);
    
    SELECT @d0, @d1, @time;
    
    USE test;
    
    # 建表
    CREATE TABLE aa_time_test(
        time2 TIMESTAMP NOT NULL DEFAULT '0000-00-00 00:00:00',
        id VARCHAR(11) NOT NULL
    )ENGINE = INNODB DEFAULT CHARSET = utf8;
    
    # 插入数据
    INSERT INTO aa_time_test
    SELECT
        @time := DATE_ADD(@time, INTERVAL 1 SECOND) AS time2,
        DATE_FORMAT(@time, '%H%i%s') AS id
    FROM 
        table_xxx # 只需要xxx表数据量够多即可
    WHERE DATE_ADD(@time, INTERVAL 1 SECOND ) <= @d1
    ORDER BY time2;
    
    # 查询
    SELECT * FROM test.aa_time_test;
    SELECT COUNT(*) FROM aa_time_test; # 86400
    DELETE FROM test.`aa_time_test` WHERE id_5 IS NOT NULL;
    
    # 新增辅助列
    CREATE TABLE table_xxx AS 
    SELECT time2, id, LPAD((FLOOR(id/5)+1)*5,6,0) AS id_5 FROM test.`aa_time_test`;

    END 2018-05-29 12:35:43

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  • 原文地址:https://www.cnblogs.com/hider/p/9104444.html
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