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  • mysql笔记

    建表语句:
    DROP TABLE IF EXISTS `paper`;
    CREATE TABLE `paper` (
    `paper_id` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL COMMENT 'paperID',
    `name` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL COMMENT 'paper名称',
    `number` int(11) NOT NULL COMMENT 'paper数量',
    `detail` varchar(200) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL COMMENT 'paper描述',
    `test1` varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
    PRIMARY KEY (`paper_id`) USING BTREE
    ) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci COMMENT = 'paper表' ROW_FORMAT = Dynamic;

    SET FOREIGN_KEY_CHECKS = 1;


    (ALTER使用)改变表结构:
    ALTER table paper add test VARCHAR(50);

    alter TABLE paper drop test;

    alter TABLE paper modify test int;

    alter TABLE paper CHANGE test test1 VARCHAR(50);

    索引使用:
    test为表字段
    alter TABLE paper add index index_test(test);

    alter TABLE paper drop index index_test
    查看所有索引 paper为表名
    show index from paper;

    复制表(包括结构,索引等等):第一步:SHOW CREATE TABLE paper 得到建表语句
    第二步:修改表名,新建表
    第三步:使用 INSERT INTO... SELECT 语句 填充数据
    例子:INSERT INTO paper_xx (paper_id,name,number,detail,test) select paper_id,name,number,detail,test from paper;

    复制表(仅数据):create table xx_日期 as select * from tablename;

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  • 原文地址:https://www.cnblogs.com/czgxxwz/p/10711539.html
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