Sql Script To set the show sort of data ( up or down )

SET QUOTED_IDENTIFIER ON
GO
SET ANSI_NULLS ON
GO

CREATE PROCEDURE dbo.MoveSequence
(
@TableName nvarchar( 200 ),
@ID  uniqueidentifier,
@isUp bit = 0 
)
 AS
/*
Yinping
2005-06-17

To move the item's sequence  up or down
@TableName  the item's table
@ID   the item's Id
@isUp   the move action '1' up ; '0' down

*/
Set @TableName = '[' + @TableName + ']'
Declare @ExecuteString nvarchar(1000)
Declare @itemSequence float
Declare @Sequence float
Declare @rowCount int

-- get its sequence
 Set @ExecuteString ='Select @Sequence = Sequence From ' + @TableName + ' Where ID = ''' + Cast( @ID as nvarchar(50)) + ''''
 Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@ID uniqueidentifier, @Sequence float output',
   @TableName,@ID,@itemSequence output
-- judge the move direction
if( @isUp = 1 )
-- move up
Begin 
 -- judge the item is the biggest
 Set @ExecuteString = 'Select @rowCount = count(*) From ' + @TableName + ' Where Sequence >' + Cast( @itemSequence As Nvarchar(100) )
 Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@rowCount int output, @itemSequence float ',
   @TableName,@rowCount output,@itemSequence

 if( @rowCount = 0 )
 Begin
  -- it is the biggest
  -- judge if existing more than one biggest
  Set @ExecuteString = 'Select @rowCount = count(*) From ' + @TableName + ' Where Sequence =' + Cast( @itemSequence As Nvarchar(100) )
  Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@rowCount int output, @itemSequence float ',
   @TableName,@rowCount output,@itemSequence
  if( @rowCount > 1)
  Begin
   -- more than one the biggest ,to add its sequence
   Set @ExecuteString ='Update ' + @TableName + ' Set Sequence = (@itemSequence + 1) Where ID = ''' + Cast( @ID as nvarchar(50)) + ''''
   Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@ID uniqueidentifier, @itemSequence float ',
   @TableName,@ID ,@itemSequence
   return
  End

  Else
  Begin
   -- only one biggest
   return
  End
  
 End

 Else if( @rowCount = 1 )
 Begin
  -- only have one item bigger than it ,meaning it is the bigger
  -- get the biggest's sequence
  Set @ExecuteString ='Select @Sequence = Sequence From ' + @TableName + ' Where ID in ( Select Top 1 ID From ' + @TableName + ' Where Sequence >' + Cast( @itemSequence As Nvarchar(100) ) + ' Order by Sequence  )'
  Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@Sequence float output, @itemSequence float ',
   @TableName,@Sequence output,@itemSequence
  -- add one to sequence
  Set @ExecuteString ='Update ' + @TableName + ' Set Sequence = (@Sequence + 1) Where ID = ''' + Cast( @ID as nvarchar(50)) + ''''
   Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@ID uniqueidentifier, @Sequence float ',
   @TableName,@ID ,@Sequence
  return
 End

 Else if( @rowCount > 1 )
 Begin
  -- more than one item bigger than it
  Set @ExecuteString ='Select @Sequence = Sum(Sequence) From ' + @TableName + ' Where ID in ( Select Top 2 ID From ' + @TableName + ' Where Sequence >' + Cast( @itemSequence As Nvarchar(100) ) + ' Order by Sequence  )'
  Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@Sequence float output, @itemSequence float ',
   @TableName,@Sequence output,@itemSequence
  Set @itemSequence = @Sequence / 2

  print @itemSequence
 
  Set @ExecuteString ='Update ' + @TableName + ' Set Sequence = @itemSequence Where ID = ''' + Cast( @ID as nvarchar(50)) + ''''
  Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@ID uniqueidentifier, @itemSequence float ',
   @TableName,@ID ,@itemSequence
  return
 End

 Else
 Begin
  -- error
  return
 End 
End

Else
-- move down
Begin 
 -- judge the item is the smallest
 Set @ExecuteString = 'Select @rowCount = count(*) From ' + @TableName + ' Where Sequence <' + Cast( @itemSequence As Nvarchar(100) )
 Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@rowCount int output, @itemSequence float ',
   @TableName,@rowCount output,@itemSequence

 if( @rowCount = 0 )
 Begin
  -- it is the smallest
  -- judge if existing more than one smallest
  Set @ExecuteString = 'Select @rowCount = count(*) From ' + @TableName + ' Where Sequence =' + Cast( @itemSequence As Nvarchar(100) )
  Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@rowCount int output, @itemSequence float ',
   @TableName,@rowCount output,@itemSequence
  if( @rowCount > 1)
  Begin
   -- more than one the smallest ,to minus its sequence
   Set @ExecuteString ='Update ' + @TableName + ' Set Sequence = (@itemSequence - 1) Where ID = ''' + Cast( @ID as nvarchar(50)) + ''''
   Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@ID uniqueidentifier, @itemSequence float ',
   @TableName,@ID ,@itemSequence
   return
  End

  Else
  Begin
   -- only one biggest
   return
  End  
 End

 Else if( @rowCount = 1 )
 Begin
  -- only have one item smaller than it ,meaning it is the smaller
  -- get the smallest's sequence
  Set @ExecuteString ='Select @Sequence = Sequence From ' + @TableName + ' Where ID in ( Select Top 1 ID From ' + @TableName + ' Where Sequence <' + Cast( @itemSequence As Nvarchar(100) ) + ' Order by Sequence  )'
  Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@Sequence float output, @itemSequence float ',
   @TableName,@Sequence output,@itemSequence
  -- minus one of its sequence
  Set @ExecuteString ='Update ' + @TableName + ' Set Sequence = (@Sequence - 1) Where ID = ''' + Cast( @ID as nvarchar(50)) + ''''
   Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@ID uniqueidentifier, @Sequence float ',
   @TableName,@ID ,@Sequence
  return
 End

 Else if( @rowCount > 1 )
 Begin
  -- more than one item smaller than it
  Set @ExecuteString ='Select @Sequence = Sum(Sequence) From ' + @TableName + ' Where ID in ( Select Top 2 ID From ' + @TableName + ' Where Sequence <' + Cast( @itemSequence As Nvarchar(100) ) + ' Order by Sequence  )'
  Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@Sequence float output, @itemSequence float ',
   @TableName,@Sequence output,@itemSequence
  Set @itemSequence = @Sequence / 2

  print @itemSequence
 
  Set @ExecuteString ='Update ' + @TableName + ' Set Sequence = @itemSequence Where ID = ''' + Cast( @ID as nvarchar(50)) + ''''
  Execute sp_executesql @ExecuteString  ,N'@TableName nvarchar( 200 ),@ID uniqueidentifier, @itemSequence float ',
   @TableName,@ID ,@itemSequence
  return
 End

 Else
 Begin
  -- error
  return
 End 
End