As I understood in normal cases we are creating a table with Primary key which is having Identity property So Rename or Delete a column which is associated with Primary Key constraint will not be possible because constraint Rules are validating column structure. Tto achieve this we have to process some steps in the following way: Let us assume TableName = 'Employee' and ColumnName = 'EmployeeId' 1. Add new column 'EmployeeId_new' in the 'Employee' table ALTER TABLE Employee ADD EmployeeId_new INT IDENTITY(1,1)

Now remove column 'EmployeeId' from 'Employee' table ALTER TABLE Employee DROP COLUMN EmployeeId This will throw error because of Primary Key Constraint rules are applicable and validating column structure. *### 'Msg 5074, Level 16, State 1, Line 1 The object [PK_dbo.Employee] is dependent on colmn [EmployeeId].'### So we have to remove the Primary Key constraint first from the table 'Employee' then we can remove the column ALTER TABLE Employee DROP constraint [PK_dbo.Employee] Now we can remove the column 'EmployeeId' from 'Employee' table as did in the previous step where we got error ALTER TABLE Employee DROP COLUMN EmployeeId Now Column 'EmployeeId' removed from table So we will Rename the newly added new column 'EmployeeId_new' with 'EmployeeId' sp_rename 'Employee.EmployeeId', 'EmployeeId_new', 'COLUMN' To rearrange the table in the same form as It was, we have to add Primary Key Constraint for the column 'EmployeeId' ALTER TABLE Employee add constraint [PK_dbo.Employee] primary key (EmployeeId)

8. 现在，带有'EmployeeId'的表'Employee'随着现有的主键约束被修改为Identity规则

根据我目前的情况，我采用这种方法。我想通过脚本插入数据后给一个主表的身份。

因为我想要追加身份，所以它总是从1开始到我想要的记录计数的结束。

--first drop column and add with identity
ALTER TABLE dbo.tblProductPriceList drop column ID 
ALTER TABLE dbo.tblProductPriceList add ID INT IDENTITY(1,1)

--then add primary key to that column (exist option you can ignore)
IF  NOT EXISTS (SELECT * FROM sys.key_constraints  WHERE object_id = OBJECT_ID(N'[dbo].[PK_tblProductPriceList]') AND parent_object_id = OBJECT_ID(N'[dbo].[tblProductPriceList]'))
    ALTER TABLE [tblProductPriceList] ADD PRIMARY KEY (id)
GO

这将创建具有identity的相同主键列

我使用了这个链接:https://blog.sqlauthority.com/2014/10/11/sql-server-add-auto-incremental-identity-column-to-table-after-creating-table/

向现有表添加主键

基本上有四个逻辑步骤。

创建一个新的Identity列。为这个新列打开Insert Identity。 将源列(希望转换为Identity的列)中的数据插入到这个新列中。 关闭新列的Insert Identity。 删除源列并将新列重命名为源列的名称。

可能会有一些更复杂的事情，比如跨多个服务器工作等。

有关步骤(使用ssms和T-sql)，请参阅下面的文章。这些步骤适用于不太熟悉T-SQL的初学者。

http://social.technet.microsoft.com/wiki/contents/articles/23816.how-to-convert-int-column-to-identity-in-the-ms-sql-server.aspx

根据设计，没有简单的方法来打开或关闭现有列的标识特性。要做到这一点，唯一干净的方法是创建一个新列并使其成为标识列，或者创建一个新表并迁移数据。

如果我们使用SQL Server Management Studio去除列“id”上的标识值，则会创建一个新的临时表，数据被移动到临时表中，旧表被删除，新表被重命名。

使用Management Studio进行更改，然后在设计器中右键单击并选择“生成更改脚本”。

你会看到这就是SQL server在后台所做的。

考虑使用SEQUENCE而不是IDENTITY。

在sql server 2014(我不知道低版本)，你可以简单地使用序列。

CREATE SEQUENCE  sequence_name START WITH here_higher_number_than_max_existed_value_in_column INCREMENT BY 1;

ALTER TABLE table_name ADD CONSTRAINT constraint_name DEFAULT NEXT VALUE FOR sequence_name FOR column_name

从这里开始:将序列作为列的默认值

为所有没有标识集的主键= bigint的表生成脚本;这将返回每个表的生成脚本列表;

SET NOCOUNT ON;

declare @sql table(s varchar(max), id int identity)

DECLARE @table_name nvarchar(max),
        @table_schema nvarchar(max);

DECLARE vendor_cursor CURSOR FOR 
SELECT
  t.name, s.name
FROM sys.schemas AS s
INNER JOIN sys.tables AS t
  ON s.[schema_id] = t.[schema_id]
WHERE EXISTS (
    SELECT
    [c].[name]
    from sys.columns [c]
    join sys.types [y] on [y].system_type_id = [c].system_type_id
    where [c].[object_id] = [t].[object_id] and [y].name = 'bigint' and [c].[column_id] = 1
) and NOT EXISTS 
(
  SELECT 1 FROM sys.identity_columns
    WHERE [object_id] = t.[object_id]
) and exists (
    select 1 from sys.indexes as [i] 
    inner join sys.index_columns as [ic]  ON  i.OBJECT_ID = ic.OBJECT_ID AND i.index_id = ic.index_id
    where object_name([ic].[object_id]) = [t].[name]
)
OPEN vendor_cursor

FETCH NEXT FROM vendor_cursor 
INTO @table_name, @table_schema

WHILE @@FETCH_STATUS = 0
BEGIN

DELETE FROM @sql

declare @pkname varchar(100),
    @pkcol nvarchar(100)

SELECT  top 1
        @pkname = i.name,
        @pkcol = COL_NAME(ic.OBJECT_ID,ic.column_id)
FROM    sys.indexes AS [i]
INNER JOIN sys.index_columns AS [ic] ON  i.OBJECT_ID = ic.OBJECT_ID AND i.index_id = ic.index_id
WHERE   i.is_primary_key = 1 and OBJECT_NAME(ic.OBJECT_ID) = @table_name

declare @q nvarchar(max) = 'SELECT  '+@pkcol+' FROM ['+@table_schema+'].['+@table_name+'] ORDER BY '+@pkcol+' DESC'

DECLARE @ident_seed nvarchar(max) -- Change this to the datatype that you are after
SET @q = REPLACE(@q, 'SELECT', 'SELECT TOP 1 @output = ')
EXEC sp_executeSql @q, N'@output bigint OUTPUT', @ident_seed OUTPUT

insert into  @sql(s) values ('BEGIN TRANSACTION')
insert into  @sql(s) values ('BEGIN TRY')

-- create statement
insert into  @sql(s) values ('create table ['+@table_schema+'].[' + @table_name + '_Temp] (')

-- column list
insert into @sql(s) 
select 
    '  ['+[c].[name]+'] ' +
    y.name + 

    (case when [y].[name] like '%varchar' then
    coalesce('('+(case when ([c].[max_length] < 0 or [c].[max_length] >= 1024) then 'max' else cast([c].max_length as varchar) end)+')','')
    else '' end)

     + ' ' +
    case when [c].name = @pkcol then 'IDENTITY(' +COALESCE(@ident_seed, '1')+',1)' else '' end + ' ' +
    ( case when c.is_nullable = 0 then 'NOT ' else '' end ) + 'NULL ' + 
    coalesce('DEFAULT ('+(
        REPLACE(
            REPLACE(
                LTrim(
                    RTrim(
                        REPLACE(
                            REPLACE(
                                REPLACE(
                                    REPLACE(
                                        LTrim(
                                            RTrim(
                                                REPLACE(
                                                    REPLACE(
                                                        object_definition([c].default_object_id)
                                                    ,' ','~')
                                                ,')',' ')
                                            )
                                        )
                                    ,' ','*')
                                ,'~',' ')
                            ,' ','~')
                        ,'(',' ')
                    )
                )
            ,' ','*')
        ,'~',' ')
    ) +
    case when object_definition([c].default_object_id) like '%get%date%' then '()' else '' end
    +
    ')','') + ','
 from sys.columns c
 JOIN sys.types y ON y.system_type_id = c.system_type_id
  where OBJECT_NAME(c.[object_id]) = @table_name and [y].name != 'sysname'
 order by [c].column_id


 update @sql set s=left(s,len(s)-1) where id=@@identity

-- closing bracket
insert into @sql(s) values( ')' )

insert into @sql(s) values( 'SET IDENTITY_INSERT ['+@table_schema+'].['+@table_name+'_Temp] ON')

declare @cols nvarchar(max)
SELECT @cols = STUFF(
    (
        select ',['+c.name+']'
        from sys.columns c
        JOIN sys.types y ON y.system_type_id = c.system_type_id
        where c.[object_id] = OBJECT_ID(@table_name)
        and [y].name != 'sysname'
        and [y].name != 'timestamp'
        order by [c].column_id
        FOR XML PATH ('')
     )
    , 1, 1, '')

insert into @sql(s) values( 'IF EXISTS(SELECT * FROM ['+@table_schema+'].['+@table_name+'])')
insert into @sql(s) values( 'EXEC(''INSERT INTO ['+@table_schema+'].['+@table_name+'_Temp] ('+@cols+')')
insert into @sql(s) values( 'SELECT '+@cols+' FROM ['+@table_schema+'].['+@table_name+']'')')

insert into @sql(s) values( 'SET IDENTITY_INSERT ['+@table_schema+'].['+@table_name+'_Temp] OFF')


insert into @sql(s) values( 'DROP TABLE ['+@table_schema+'].['+@table_name+']')

insert into @sql(s) values( 'EXECUTE sp_rename N''['+@table_schema+'].['+@table_name+'_Temp]'', N'''+@table_name+''', ''OBJECT''')

if ( @pkname is not null ) begin
    insert into @sql(s) values('ALTER TABLE ['+@table_schema+'].['+@table_name+'] ADD CONSTRAINT ['+@pkname+'] PRIMARY KEY CLUSTERED (')
    insert into @sql(s)
        select '  ['+COLUMN_NAME+'] ASC,' from information_schema.key_column_usage
        where constraint_name = @pkname
        GROUP BY COLUMN_NAME, ordinal_position
        order by ordinal_position

    -- remove trailing comma
    update @sql set s=left(s,len(s)-1) where id=@@identity
    insert into @sql(s) values ('  )')
end

insert into  @sql(s) values ('--Run your Statements')
insert into  @sql(s) values ('COMMIT TRANSACTION')
insert into  @sql(s) values ('END TRY')
insert into  @sql(s) values ('BEGIN CATCH')
insert into  @sql(s) values ('        ROLLBACK TRANSACTION')
insert into  @sql(s) values ('        DECLARE @Msg NVARCHAR(MAX)  ')
insert into  @sql(s) values ('        SELECT @Msg=ERROR_MESSAGE() ')
insert into  @sql(s) values ('        RAISERROR(''Error Occured: %s'', 20, 101,@msg) WITH LOG')
insert into  @sql(s) values ('END CATCH')

declare @fqry nvarchar(max)

-- result!
SELECT @fqry = (select char(10) + s from @sql order by id FOR XML PATH (''))


SELECT @table_name as [Table_Name], @fqry as [Generated_Query]
PRINT 'Table: '+@table_name
EXEC sp_executeSql @fqry

    FETCH NEXT FROM vendor_cursor 
    INTO @table_name, @table_schema
END 
CLOSE vendor_cursor;
DEALLOCATE vendor_cursor;