PHP+MYSQL插入数据 检查是否重复,该如何解决
PHP+MYSQL插入数据 检查是否重复
PHP+MYSQL插入数据 检查是否重复 是从excel里面导入的数据 别人新导入的可能会跟已有的数据重复 用的PHP-ExcelReader导入的
------解决方案--------------------
修改一下数据表就行了：
把你认为可能会存在重复的字段 设置为“UNIQUE”索引，这样就可以避免重复了。
------解决方案--------------------
select count(*) from tbl_name group by 不允许重复的字段
结果大于 1 ，就表示有重复
------解决方案--------------------
表中filename字段已经有重复数据了。创建唯一索引失败。
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