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  • mysql判断表字段或索引是否存在,然后修改

    判断字段是否存在:

    DROP PROCEDURE IF EXISTS schema_change;  
    DELIMITER //
    CREATE PROCEDURE schema_change() BEGIN 
    DECLARE  CurrentDatabase VARCHAR(100);
    SELECT DATABASE() INTO CurrentDatabase;
    IF NOT EXISTS (SELECT * FROM information_schema.columns WHERE table_schema=CurrentDatabase AND table_name = 'rtc_order' AND column_name = 'IfUpSend') THEN  
        ALTER TABLE rtc_order
        ADD COLUMN `IfUpSend` BIT  NOT NULL  DEFAULT 0 COMMENT '是否上传 是否上传';
    END IF;  
    END//  
    DELIMITER ;  
    CALL schema_change();

    判断索引是否存在:

    DROP PROCEDURE IF EXISTS schema_change;  
    DELIMITER //
    CREATE PROCEDURE schema_change() BEGIN 
    DECLARE  CurrentDatabase VARCHAR(100);
    SELECT DATABASE() INTO CurrentDatabase;
    IF NOT EXISTS (SELECT * FROM information_schema.statistics WHERE table_schema=CurrentDatabase AND table_name = 'rtc_phototype' AND index_name = 'index_name') THEN  
       ALTER TABLE `rtc_Phototype` ADD INDEX index_name ( `imgtype` );
    END IF;  
    END//  
    DELIMITER ;  
    CALL schema_change();
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  • 原文地址:https://www.cnblogs.com/nizuimeiabc1/p/11031086.html
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