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mysql通用分页存储过程遇到的问题

2018-06-21 06:54:14来源：未知阅读 ()

DELIMITER $$

USE `tsb_asksys`$$

DROP PROCEDURE IF EXISTS `P_viewPage`$$

CREATE DEFINER=`root`@`localhost` PROCEDURE `P_viewPage`(  
       $TableName VARCHAR(200),/*表名*/
       $FieldList VARCHAR(2000),  /*显示列名*/
       $PrimaryKey VARCHAR(100),  /*单一主键或唯一值键*/
       $WhereStr VARCHAR(1000),  /*查询条件 不含'where'字符*/
       $OrderStr VARCHAR(1000),  /*排序 不含'order by'字符，如id asc,userid desc，当@SortType=3时生效*/
       $SortType INT,  /*排序规则 1:正序asc 2:倒序desc 3:多列排序*/
       $RecorderCount INT,  /*记录总数 0:会返回总记录*/
       $PageSize INT,  /*每页输出的记录数*/
       $PageIndex INT,  /*当前页数*/
OUT    $TotalCount INTEGER,  /*返回记录总数*/
OUT    $TotalPageCount INTEGER  /*返回总页数*/
)
BEGIN  
IF !(($TableName IS NULL OR $TableName='') OR ($FieldList IS NULL OR $FieldList='') OR ($PrimaryKey IS NULL OR $PrimaryKey='') OR $SortType < 1 OR $SortType >3 OR $RecorderCount < 0 OR $PageSize < 0 OR $PageIndex < 0) THEN  
IF ($WhereStr IS NULL OR $WhereStr='') THEN  
  SET @new_where1 = ' ' ;  
  SET @new_where2 = ' WHERE ' ;  
ELSE  
  SET @new_where1 =CONCAT(' WHERE ',$WhereStr);  
  SET @new_where2 =CONCAT(' WHERE ',$WhereStr,' AND ');  
END IF;  
IF $OrderStr='' OR $SortType = 1 OR $SortType = 2 THEN  
  IF $SortType = 1 THEN  
       SET @new_order =CONCAT(' ORDER BY ',$PrimaryKey,' ASC' );  
    END IF;  
  IF $SortType = 2 THEN  
       SET @new_order =CONCAT(' ORDER BY ',$PrimaryKey,' DESC');  
    END IF;  
ELSE  
  SET @new_order =CONCAT(' ORDER BY ',$OrderStr);  
END IF;  
SET @SqlCount = CONCAT('SELECT COUNT(*) into @TotalCount FROM ',$TableName,@new_where1);  
SET @SqlCount1 = CONCAT('SELECT CEILING((COUNT(*)+0.0)/',$PageSize,') into @TotalPageCount FROM ',$TableName,@new_where1);  
IF $RecorderCount = 0 THEN  
     PREPARE stmt1 FROM @SqlCount;  
     EXECUTE stmt1;  
     SET $TotalCount=@TotalCount;  
     PREPARE stmt1 FROM @SqlCount1;  
     EXECUTE stmt1;  
     SET $TotalPageCount=@TotalPageCount;  
ELSE  
  SET $TotalCount = $RecorderCount;  
END IF;  
IF $PageIndex > CEILING(($TotalCount+0.0)/$PageSize) THEN  
  SET $PageIndex = CEILING(($TotalCount+0.0)/$PageSize);  
END IF;  
IF $PageIndex = 0 OR $PageIndex = 1 THEN  
   SET @Sql=CONCAT('SELECT ',$FieldList,' FROM ',$TableName,@new_where1,@new_order,' limit ',$PageSize);  
ELSE  
  IF $SortType = 1 THEN  
       SET @Sql=CONCAT('SELECT ',$FieldList,' FROM ',$TableName,@new_where2,$PrimaryKey,' > (SELECT max(',$PrimaryKey,') FROM (SELECT ',$PrimaryKey,' FROM ',$TableName,@new_where1,@new_order,' limit ',$PageSize*($PageIndex-1),' ) AS TMP) ',@new_order,' limit ',$PageSize);  
  END IF;  
  IF $SortType = 2 THEN  
       SET @Sql=CONCAT('SELECT ',$FieldList,' FROM ',$TableName,@new_where2,$PrimaryKey,' < (SELECT MIN(',$PrimaryKey,') FROM (SELECT ',$PrimaryKey,' FROM ',$TableName,@new_where1,@new_order,' limit ',$PageSize*($PageIndex-1),' ) AS TMP) ',@new_order,' limit ',$PageSize);  
    END IF;  
  IF $SortType = 3 THEN  
      /*IF INSTR($OrderStr,',') > 0 THEN  
            SET @Sql=CONCAT('SELECT ',$FieldList,' FROM ',$TableName,@new_where2,$PrimaryKey,' NOT IN (SELECT ',$PrimaryKey,' FROM (SELECT ',$PrimaryKey,' FROM ',$TableName,@new_where1,@new_order,' limit ',$PageSize*($PageIndex-1),' ) a)',@new_order,' limit ',$PageSize);  
      ELSE  
            SET @new_order =CONCAT(' ORDER BY ',$PrimaryKey,' ASC' );  
            SET @Sql=CONCAT('SELECT ',$FieldList,' FROM ',$TableName,@new_where2,$PrimaryKey,' > (SELECT max(',$PrimaryKey,') FROM (SELECT ',$PrimaryKey,' FROM ',$TableName,@new_where1,@new_order,' limit ',$PageSize*($PageIndex-1),' ) AS TMP) ',@new_order,' limit ',$PageSize);  
      END IF;*/
      SET @Sql=CONCAT('SELECT ',$FieldList,' FROM ',$TableName,@new_where2,$PrimaryKey,' NOT IN (SELECT ',$PrimaryKey,' FROM (SELECT ',$PrimaryKey,' FROM ',$TableName,@new_where1,@new_order,' limit ',$PageSize*($PageIndex-1),' ) a)',@new_order,' limit ',$PageSize);
  END IF;  
END IF;  
PREPARE stmt2 FROM @Sql;  
EXECUTE stmt2;  
END IF;  
END$$

DELIMITER ;

以上存储过程是在网上找的，使用过程中遇到的问题是，当查询第二页及以后页内容时无法获得。

以下是解决办法，备注中说的非常清楚：

static public DataTable getAllUser(int PageSize, int CurrPageIndex, out int AllRecordCount, String _SearchWhere)
        {
            using (MySqlCommand cmd = new MySqlCommand("P_viewPage"))
            {
                cmd.CommandType = CommandType.StoredProcedure;

                //设置表名称：
                System.Text.StringBuilder TableName = new System.Text.StringBuilder();
                TableName.Append(" GQShowV_UserInfoForAdmin t1 ");
                cmd.Parameters.AddWithValue("@$TableName", TableName.ToString());//对表名参数赋值

                //设置字段名称：
                System.Text.StringBuilder myfld_str = new System.Text.StringBuilder();
                myfld_str.Append("  t1.RecordID, t1.UserID, t1.LoginID, t1.Nickname,t1.SexID_Exp,t1.UserEmail_Exp,t1.CreateDate,t1.UserName,t1.Phone, t1.Tel,t1.IsAdmin_Exp ");
                cmd.Parameters.AddWithValue("@$FieldList", myfld_str.ToString());//对字段参数赋值

                //设置按哪个字段进行排序
                cmd.Parameters.AddWithValue("@$OrderStr", "t1.createDate DESC");// --排序 不含'order by'字符，如id asc,userid desc，当@SortType=3时生效

                /*设置排序方式，规则说明：1是按照PrimaryKey正序asc；2按照PrimaryKey倒序desc；
                3按照非关键字或多关键字排序，比如日期，排序字段后可跟asc或desc，如t1.createDate DESC或t1.createDate DESC,t1.other asc
                另外请注意：排序方式只有1,2,3，其他数字不会从数据库中读出数据*/
                cmd.Parameters.AddWithValue("@$SortType", 3);//--排序规则 1:正序asc 2:倒序desc 3:多列排序

                //设置主表的关键字，切记：主键前不要加前缀，否则第二页及以后页内容无法读出
                cmd.Parameters.AddWithValue("@$PrimaryKey", "UserID");//t1.UserID 第二页不会显示出来，因为有前缀
                //设置总查询记录数：为0时，查询实际记录，主要解决表记录非常大，那么可以限制只查询10万条记录这样的问题
                cmd.Parameters.AddWithValue("@$RecorderCount", 0);
                //设置查询条件
                System.Text.StringBuilder query_where = new StringBuilder();//保存查询条件 
                query_where.Append(" (1 = 1) ");


                if (!String.IsNullOrEmpty(_SearchWhere))
                {
                    query_where.AppendFormat("and (t1.UserName LIKE N'%{0}%')", _SearchWhere);
                }

                cmd.Parameters.AddWithValue("@$WhereStr", query_where.ToString());//设置查询条件

                //设置每页要显示的记录数
                cmd.Parameters.AddWithValue("@$PageSize", PageSize);
                //设置要显示的页码：
                cmd.Parameters.AddWithValue("@$PageIndex", CurrPageIndex);
                //保存查询到的总记录数

                MySqlParameter record_num = new MySqlParameter();
                record_num = cmd.Parameters.Add(new MySqlParameter("@$TotalCount", SqlDbType.Int));
                record_num.Direction = ParameterDirection.Output;
                //
                int _TotalPageCount = 0;
                MySqlParameter TotalPageCount = new MySqlParameter();
                TotalPageCount = cmd.Parameters.Add(new MySqlParameter("@$TotalPageCount", SqlDbType.Int));
                TotalPageCount.Direction = ParameterDirection.Output;

                using (DataTable dt = ObjectMindDBForMysql.MySqlHelper.GetData(cmd))
                {
                    AllRecordCount = int.Parse(cmd.Parameters["@$TotalCount"].Value.ToString());
                    _TotalPageCount = int.Parse(cmd.Parameters["@$TotalPageCount"].Value.ToString());
                    return dt;
                }
            }
        }