MySQL数据修复常见SQL总结
# 表备份SQL
create table tableName_20200604_bak as select * from tableNmael WHERE id IN('202003301526315761','202003310858300900','202003301646584072');
# 新增字段
ALTER TABLE tableName
ADD COLUMN column1 VARCHAR(200) NULL DEFAULT '' COMMENT '备注' ,
ADD COLUMN column2 datetime NULL COMMENT '备注' ,
ADD COLUMN column3 int(11) DEFAULT 0 COMMENT '备注' ;
# 增加索引
ALTER TABLE tableName ADD INDEX iddex_name (column_name);
#删除唯一约束
drop index unique_name on tableName;
# 增加唯一约束
alter table tableName add unique(column_name)
#修复数据
update tableName set column1 = concat('xxxx',column2);
update tableName set column1 = 'xxx' where column2 like 'xxx%';
