• 存储过程


    提前这个存储过程,真的是让我心里很是委屈,做开发这么久了,我竟然不会存储过程,纠结了我两天,下面就来看看存储过程

    存储过程就是一种特殊的函数,基本上没有返回值,如果要有返回值,则必须是0,1

    存储过程是存放在服务器端的,一旦存储过程建立之后,则以后就可以随时使用,不在进行编译了

    创建存储过程

    Create Proc Pro_Table  //创建一个存储过程

    (@UserId Int) // 定义参数

    as

    Begin

    Declare @Sql Navrchar(2000);  // 声明一个变量

    set @Sql='select * from car';

    Exec(@Sql) //执行存储过程

    Print(@Sql)   //打印

    End

    Go

    带分页的存储过程,这个这么我好久了

    Alter proc  Pro_CarComment
    (
    @UserId int,
    @PageSize int,                     --每页多少条记录
    @PageIndex int = 1 ,               --指定当前为第几页
    @TotalRecord int output,            --返回总记录数
    @TotalPageCount int output         --返回总页数
    )
    as
    Begin
    
    Declare @StartRecord int;
    Declare @EndRecord int;
    Declare @TotalCountSql nvarchar(500);
    Declare @SqlString nvarchar(2000);
    set @StartRecord =(@PageIndex-1)*@PageSize+1
    set @EndRecord =@StartRecord +@PageSize-1
    set @TotalCountSql='select count(*) from (select cm.id,cm.Content,cm.CarId ,cm.CreateTime from
    (SELECT   UserProfileId,[carid],max(id) as id
    FROM [BusinessData].[dbo].[CarComment]
    group by [carid],  UserProfileId) as temp ,[CarComment] as cm
    where  temp.CarId=cm.CarId  and temp.id=cm.id)temp2,car as c
    where temp2.CarId=c.Id and c.UserId='+CAST( @UserId as varchar)
    set @SqlString='select,row_number() over (order by desc) as rowId, c.id as cid,c.carname,temp2.Id as cmid,temp2.content,temp2.CreateTime as cmtime from
    (select cm.id,cm.Content,cm.CarId ,cm.CreateTime from
    (SELECT   UserProfileId,[carid],max(id) as id
    FROM [BusinessData].[dbo].[CarComment]
    group by [carid],  UserProfileId) as temp ,[CarComment] as cm
    where  temp.CarId=cm.CarId  and temp.id=cm.id)temp2,car as c
    where temp2.CarId=c.Id and c.UserId='+CAST( @UserId as varchar)
    
    EXEC sp_executesql @totalCountSql,N'@TotalRecord int out',@TotalRecord output;--返回总记录数
    
    set @TotalPageCount=(@TotalRecord+@PageSize-1)/@PageSize
    set @SqlString ='select * from ('+@SqlString+')as t where rowId between '+ltrim(str(@StartRecord))+' and '+ ltrim(str(@EndRecord));
    
    Exec(@SqlString)    
        print @SqlString
        print @TotalRecord
        print @TotalPageCount
        end
        Go

    下面在记一个通用的分页存储过程

    ALTER(Create) procedure [dbo].[p_fen_ye] @table varchar(20),@id varchar(20),@orderby int,@pagesize int,@pageno int,@iswhere int,@where varchar(500)
    as
    declare @by varchar(10)
    set @by='asc'
    if(@orderby=1)
    begin
    set @by='desc';
    end
    declare @start varchar(10);
    set @start = cast(((@pageno-1)*@pagesize) as varchar);
    declare @sql varchar(500);
    if(@iswhere!=0)
    begin
    set @sql='select top '+cast(@pagesize as varchar)+' * from '+@table+' where '+@id+' not in (select top '+@start+' '+@id+' from '+@table+' where '+@where+' order by '+@id+' '+@by+') and '+@where+' order by '+@id+' '+@by;
    end
    else
    begin
    set @sql='select top '+cast(@pagesize as varchar)+' * from '+@table+' where '+@id+' not in (select top '+@start+' '+@id+' from '+@table+' order by '+@id+' '+@by+') order by '+@id+' '+@by;
    end
    execute (@sql)

    这个还有一个朋友给我的通用的分页存储过程,只需要传2个参数

    CREATE   PROCEDURE Pro_CarComment
    @page_size int ,--页面大小
    @current_page int  output-- 当前第几页
    as 
    begin 
         declare @page_count int--页面总数
         declare @last_page  int--尾页
         declare @first_page   int--首页
         declare @sql nvachar(2000) 
        select @page_count =  COUNT(*) from Employee 
         if( @page_count %@page_size=0)
            begin
              set @last_page = @page_count / @page_size
             end
          if (@page_count %@page_size !=0)
             begin
             set @last_page = @page_count/@page_size +1
              end
         if ( @current_page <=0)
          begin 
              select  @first_page=1, @current_page = @first_page
             end 
          if (@current_page >= @last_page)
            begin
              set @current_page= @last_page
             end 
        select  top(@page_size) *
       from Employee where Employee_no not in ( select  top(@page_size * (@current_page-1)) Employee_no from  Employee )
    end

    依个人习惯创建分页存储过程,再追加一个吧,目前简单的存储过程会创建了

    -创建分页存储过程
    -------------------------------------------------------------------
    CREATE PROC [dbo].[sp_PageView]
        @tbname SYSNAME ,               --要分页显示的表名   
        @FieldKey NVARCHAR(1000) ,      --用于定位记录的主键(惟一键)字段,可以是逗号分隔的多个字段   
        @PageCurrent INT = 1 ,               --要显示的页码   
        @PageSize INT = 10 ,                --每页的大小(记录数)   
        @FieldShow NVARCHAR(1000) = '' ,      --以逗号分隔的要显示的字段列表,如果不指定,则显示所有字段   
        @FieldOrder NVARCHAR(1000) = '' ,      --以逗号分隔的排序字段列表,可以指定在字段后面指定DESC/ASC   用于指定排序顺序   
        @Where NVARCHAR(1000) = '' ,     --查询条件   
        @RecordCount INT OUTPUT             --总页数   
    AS 
        DECLARE @PageCount AS INT
        SET NOCOUNT ON   
    --检查对象是否有效   
        IF OBJECT_ID(@tbname) IS NULL 
            BEGIN   
                RAISERROR(N'对象"%s"不存在',1,16,@tbname)   
                RETURN   
            END   
        IF OBJECTPROPERTY(OBJECT_ID(@tbname), N'IsTable') = 0
            AND OBJECTPROPERTY(OBJECT_ID(@tbname), N'IsView') = 0
            AND OBJECTPROPERTY(OBJECT_ID(@tbname), N'IsTableFunction') = 0 
            BEGIN   
                RAISERROR(N'"%s"不是表、视图或者表值函数',1,16,@tbname)   
                RETURN   
            END   
       
    --分页字段检查   
        IF ISNULL(@FieldKey, N'') = '' 
            BEGIN   
                RAISERROR(N'分页处理需要主键(或者惟一键)',1,16)   
                RETURN   
            END   
       
    --其他参数检查及规范   
        IF ISNULL(@PageCurrent, 0) < 1 
            SET @PageCurrent = 1   
        IF ISNULL(@PageSize, 0) < 1 
            SET @PageSize = 10   
        IF ISNULL(@FieldShow, N'') = N'' 
            SET @FieldShow = N'*'   
        IF ISNULL(@FieldOrder, N'') = N'' 
            SET @FieldOrder = N''   
        ELSE 
            SET @FieldOrder = N'ORDER BY ' + LTRIM(@FieldOrder)   
        IF ISNULL(@Where, N'') = N'' 
            SET @Where = N''   
        ELSE 
            SET @Where = N'WHERE (' + @Where + N')'   
       
    --如果@PageCount为NULL值,则计算总页数(这样设计可以只在第一次计算总页数,以后调用时,把总页数传回给存储过程,避免再次计算总页数,对于不想计算总页数的处理而言,可以给@PageCount赋值)   
        IF @PageCount IS NULL 
            BEGIN   
                DECLARE @sql NVARCHAR(4000)   
                SET @sql = N'SELECT @RecordCount=COUNT(*)' + N' FROM ' + @tbname
                    + N' ' + @Where   
                EXEC sp_executesql 
                    @sql ,
                    N'@RecordCount int OUTPUT' ,
                    @RecordCount OUTPUT   
    
                SET @PageCount = ( @RecordCount + @PageSize - 1 ) / @PageSize   
            END   
       
    --计算分页显示的TOPN值   
        DECLARE
            @TopN VARCHAR(20) ,
            @TopN1 VARCHAR(20)   
        SELECT
            @TopN = @PageSize ,
            @TopN1 = ( @PageCurrent - 1 ) * @PageSize   
       
    --第一页直接显示   
        IF @PageCurrent = 1 
            EXEC(N'SELECT TOP '+@TopN   
            +N' '+@FieldShow   
            +N' FROM '+@tbname   
            +N' '+@Where   
            +N' '+@FieldOrder)   
        ELSE 
            BEGIN   
        --处理别名   
                IF @FieldShow = N'*' 
                    SET @FieldShow = N'a.*'   
       
        --生成主键(惟一键)处理条件   
                DECLARE
                    @Where1 NVARCHAR(4000) ,
                    @Where2 NVARCHAR(4000) ,
                    @s NVARCHAR(1000) ,
                    @Field SYSNAME   
                SELECT
                    @Where1 = N'' ,
                    @Where2 = N'' ,
                    @s = @FieldKey   
                WHILE CHARINDEX(N',', @s) > 0 
                    SELECT
                        @Field = LEFT(@s, CHARINDEX(N',', @s) - 1) ,
                        @s = STUFF(@s, 1, CHARINDEX(N',', @s), N'') ,
                        @Where1 = @Where1 + N' AND a.' + @Field + N'=b.' + @Field ,
                        @Where2 = @Where2 + N' AND b.' + @Field + N' IS NULL' ,
                        @Where = REPLACE(@Where, @Field, N'a.' + @Field) ,
                        @FieldOrder = REPLACE(@FieldOrder, @Field, N'a.' + @Field) ,
                        @FieldShow = REPLACE(@FieldShow, @Field, N'a.' + @Field)   
                SELECT
         --@Where=REPLACE(@Where,@s,N'a.'+@s),   
                    @FieldOrder = REPLACE(@FieldOrder, @s, N'a.' + @s) ,
                    @FieldShow = REPLACE(@FieldShow, @s, N'a.' + @s) ,
                    @Where1 = STUFF(@Where1 + N' AND a.' + @s + N'=b.' + @s, 1, 5,
                                    N'') ,
                    @Where2 = CASE WHEN @Where = '' THEN N'WHERE ('
                                   ELSE @Where + N' AND ('
                              END + N'b.' + @s + N' IS NULL' + @Where2 + N')'   
        --执行查询 
      
                EXEC(N'SELECT TOP '+@TopN   
                +N' '+@FieldShow   
                +N' FROM '+@tbname   
                +N' a LEFT JOIN(SELECT TOP '+@TopN1   
                +N' '+@FieldKey   
                +N' FROM '+@tbname   
                +N' a '+@Where   
                +N' '+@FieldOrder   
                +N')b ON '+@Where1   
                +N' '+@Where2   
                +N' '+@FieldOrder)   
            END   
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  • 原文地址:https://www.cnblogs.com/llxy/p/3937672.html
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