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具体的upgrade脚本如下:
动态删除索引
DROP PROCEDURE IF EXISTS UPGRADE;DELIMITER $$
CREATE PROCEDURE UPGRADE()BEGIN-- RESOURCE.AUDIO_ATTRIBUTEIF EXISTS(SELECT * FROM INFORMATION_SCHEMA.STATISTICS WHERE TABLE_SCHEMA = 'RESOURCE' AND TABLE_NAME = 'AUDIO_ATTRIBUTE' AND INDEX_NAME = 'resource_publish_resource_id_index')THEN ALTER TABLEAUDIO_ATTRIBUTE
DROP INDEX resource_publish_resource_id_index;END IF; END$$
DELIMITER ;CALL UPGRADE();DROP PROCEDURE IF EXISTS UPGRADE;动态添加字段
DROP PROCEDURE IF EXISTS UPGRADE;
DELIMITER $$
CREATE PROCEDURE UPGRADE()BEGIN-- HOMEWORK.HOMEWORK_QUESTION_GROUP.FROM_IDIF NOT EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'HOMEWORK' AND TABLE_NAME = 'HOMEWORK_QUESTION_GROUP' AND COLUMN_NAME = 'FROM_ID')THEN ALTER TABLEHOMEWORK_QUESTION_GROUP
ADD COLUMN FROM_ID VARCHAR(50) NULL;END IF; -- HOMEWORK.HOMEWORK_QUESTION_GROUP.QUESTION_TYPE
IF NOT EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'HOMEWORK' AND TABLE_NAME = 'HOMEWORK_QUESTION_GROUP' AND COLUMN_NAME = 'QUESTION_TYPE')THEN ALTER TABLEHOMEWORK_QUESTION_GROUP
ADD COLUMN QUESTION_TYPE VARCHAR(50) NULL;END IF; -- HOMEWORK.HOMEWORK_QUESTION_GROUP.DIFFICULTY
IF NOT EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'HOMEWORK' AND TABLE_NAME = 'HOMEWORK_QUESTION_GROUP' AND COLUMN_NAME = 'DIFFICULTY')THEN ALTER TABLEHOMEWORK_QUESTION_GROUP
ADD COLUMN DIFFICULTY VARCHAR(50) NULL;END IF; END$$
DELIMITER ;CALL UPGRADE();DROP PROCEDURE IF EXISTS UPGRADE;其他语法类似,主要区分EXISTS和 NOT EXISTS的用法。
转载于:https://blog.51cto.com/13545923/2053348