数据库操作 1、查询多条记录,返回:二维数组 $result = $model->select(); $result = $model->field()->select(); $result = $model->where()->select(); $result = $model->order()->select(); $result = $model->limit()->select(); $result = $model->field()->where()->order()->limit()->select(); 2、删除记录,返回:受影响的行数 $result = $model->delete(); $result = $model->where()->delete(); 3、添加记录,返回:主键值(主键自增长)、受影响的行数(主键不是自增长) $result = $model->add(一维关联的数组); $result = $model->data(一维关联的数组)->add(); 4、查询一条记录,返回:一维关联数组 $result = $model->find(); $result = $model->field()->find(); $result = $model->where()->find(); 5、修改记录,返回:受影响的行数 $result = $model->save(一维关联数组); $result = $model->where()->save(一维关联数组); 6、执行select语句,返回:二维数组 $result = M()->query("select语句"); 7、执行insert、update、delete语句,返回:受影响的行数 $result = M()->execute("insert|update|delete语句"); 8、聚合查询,返回:数字 $result = $model->where()->count(); $result = $model->where()->sum(字段); $result = $model->where()->avg(字段); $result = $model->where()->max(字段); $result = $model->where()->min(字段); 9、多表查询 $result = $model->join("多表查询")->select(); $result = $model->join("多表查询")->find(); $newsInfo = M("newsarticles")->join("newstypes on newsarticles.typeId=newstypes.typeId")->select(); 10、修改一个指定的字段 $result = $model->where()->save(一维关联数组); $result = $model->where()->setField("字段名","字段值"); 11、查询一个指定的字段 $result = $model->where()->getField("字段名"); 12、让字段值递增 $result = $model->where()->setInc("字段名");//让字段值加1 $result = $model->where()->setInc("字段名",3);//让字段值加3 13、让字段值递减 $result = $model->where()->setDec("字段名");//让字段值减1 $result = $model->where()->setDec("字段名",3);//让字段值减3 SELECT * FROM [user] WHERE u_name LIKE '%三%' Sql代码 select * from user where username like '%huxiao'; select * from user where username like 'huxiao%'; select * from user where username like '%huxiao%'; 另外,如果需要找出u_name中既有“三”又有“猫”的记录,请使用and条件 SELECT * FROM [user] WHERE u_name LIKE ‘%三%’ AND u_name LIKE ‘%猫%’ 若使用 SELECT * FROM [user] WHERE u_name LIKE ‘%三%猫%’ 虽然能搜索出“三脚猫”,但不能搜索出符合条件的“张猫三”。 _:表示任意单个字符。匹配单个任意字符,它常用来限制表达式的字符长度语句:(可以代表一个中文字符) Sql代码 select * from user where username like '_'; |
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