今天小編為大家分享一篇關(guān)于Mysql動態(tài)更新數(shù)據(jù)庫腳本的示例講解，具體的upgrade腳本如下：

動態(tài)刪除索引

DROP PROCEDURE IF EXISTS UPGRADE;DELIMITER $$CREATE PROCEDURE UPGRADE()BEGIN-- RESOURCE.AUDIO_ATTRIBUTE IF EXISTS(SELECT * FROM INFORMATION_SCHEMA.STATISTICS WHERE TABLE_SCHEMA = 'RESOURCE' AND TABLE_NAME = 'AUDIO_ATTRIBUTE' AND INDEX_NAME = 'resource_publish_resource_id_index') THEN ALTER TABLE `AUDIO_ATTRIBUTE` DROP INDEX resource_publish_resource_id_index; END IF;END$$DELIMITER ;CALL UPGRADE();DROP PROCEDURE IF EXISTS UPGRADE;

動態(tài)添加字段

DROP PROCEDURE IF EXISTS UPGRADE;DELIMITER $$CREATE PROCEDURE UPGRADE()BEGIN-- HOMEWORK.HOMEWORK_QUESTION_GROUP.FROM_ID IF NOT EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'HOMEWORK' AND TABLE_NAME = 'HOMEWORK_QUESTION_GROUP' AND COLUMN_NAME = 'FROM_ID') THEN ALTER TABLE `HOMEWORK_QUESTION_GROUP` ADD COLUMN FROM_ID VARCHAR(50) NULL; END IF;-- HOMEWORK.HOMEWORK_QUESTION_GROUP.QUESTION_TYPE IF NOT EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'HOMEWORK' AND TABLE_NAME = 'HOMEWORK_QUESTION_GROUP' AND COLUMN_NAME = 'QUESTION_TYPE') THEN ALTER TABLE `HOMEWORK_QUESTION_GROUP` ADD COLUMN QUESTION_TYPE VARCHAR(50) NULL; END IF;-- HOMEWORK.HOMEWORK_QUESTION_GROUP.DIFFICULTY IF NOT EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'HOMEWORK' AND TABLE_NAME = 'HOMEWORK_QUESTION_GROUP' AND COLUMN_NAME = 'DIFFICULTY') THEN ALTER TABLE `HOMEWORK_QUESTION_GROUP` ADD COLUMN DIFFICULTY VARCHAR(50) NULL; END IF;END$$DELIMITER ;CALL UPGRADE();DROP PROCEDURE IF EXISTS UPGRADE;

其他語法類似，主要區(qū)分EXISTS和NOT EXISTS的用法。

---

以上就是本文的全部內(nèi)容，希望對大家的學(xué)習(xí)有所幫助，如果大家有任何疑問請給我留言，小編會及時(shí)回復(fù)大家的。后面小編會分享更多運(yùn)維方面的干貨，感興趣的朋友走一波關(guān)注哩~

總結(jié)

以上是生活随笔為你收集整理的mysql begin end 用法_超实用的Mysql动态更新数据库脚本的示例讲解（推荐）的全部內(nèi)容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網(wǎng)站內(nèi)容還不錯(cuò)，歡迎將生活随笔推薦給好友。