本篇文章将通过存储过程来判断列（字段）是否存在。请看详情。
推荐课程：MySQL教程。
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();
mysql 判断字段否存在，如果存在就修改字段：
DROP PROCEDURE IF EXISTS proc_tempPro;if(@count>0) THEN alter table 表名 change column `旧列名` `新列名` varchar(30) comment '字段说明';end if;end;call proc_tempPro;DROP PROCEDURE IF EXISTS proc_tempPro;
通过存储过程判断字段是否存在，不存在则增加：
DROP PROCEDURE IF EXISTS pro_AddColumn;CREATE PROCEDURE pro_AddColumn() BEGINIF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name='component' AND COLUMN_NAME='PRINT_CHECK_STATUS') THENALTER TABLE component ADD PRINT_CHECK_STATUS int(10) default 0;END IF;IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name='component' AND COLUMN_NAME='PRINT_CHECK_TIME') THENALTER TABLE component ADD PRINT_CHECK_TIME datetime NULL;END IF;IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE ta<mark style="color:transparent">来4源gaodaimacom搞#代%码*网</mark>ble_schema=podcloud AND table_name='component' AND COLUMN_NAME='PRINT_CHECK_BACK_REASON') THENALTER TABLE component ADD PRINT_CHECK_BACK_REASON varchar(500) default null;END IF;END;CALL pro_AddColumn;DROP PROCEDURE pro_AddColumn;------------------------------------------------------------------------------------------------DROP PROCEDURE IF EXISTS pro_AddIndex; DELIMITER; CREATE PROCEDURE pro_AddIndex() BEGIN 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 pro_AddIndex(); Drop procedure pro_AddIndex;
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