我有SQL Server数据库,我想改变标识列,因为它开始了 有一个大数字10010,它与另一个表相关,现在我有200条记录,我想在记录增加之前修复这个问题。

更改或重置该列的最佳方法是什么?


当前回答

如果你的问题答对了,你想做的是

update table
set identity_column_name = some value

让我告诉你,这不是一个简单的过程,使用它是不可取的,因为它可能有一些相关的外键。

但这里有一些步骤,请采取备份表

步骤1-选择表的设计视图

步骤2-关闭标识列

现在可以使用更新查询了。

现在重做第1步和第2步,并打开标识列

参考

其他回答

您还可以使用SET IDENTITY INSERT来允许您将值插入到标识列中。

例子:

SET IDENTITY_INSERT dbo.Tool ON
GO

然后你可以在单位列中插入你需要的值。

如果你的问题答对了,你想做的是

update table
set identity_column_name = some value

让我告诉你,这不是一个简单的过程,使用它是不可取的,因为它可能有一些相关的外键。

但这里有一些步骤,请采取备份表

步骤1-选择表的设计视图

步骤2-关闭标识列

现在可以使用更新查询了。

现在重做第1步和第2步,并打开标识列

参考

不允许更新: 但是你可以

用正确的键插入新数据 删除注册

Import:所有字段必须在insert into中声明 示例:reg 5必须更改为4:

    set IDENTITY_INSERT Gastos_ReclamacionCausa on
insert into Gastos_ReclamacionCausa
    (IDCausa,TextoCombo,Asunto,Mensaje,EsBaja)
select 4,TextoCombo,Asunto,Mensaje,EsBaja from Gastos_ReclamacionCausa where idcausa=5
delete from  Gastos_ReclamacionCausa where idcausa = 5
set IDENTITY_INSERT Gastos_ReclamacionCausa off

c#程序员使用命令构建器的完整解决方案

首先,你要知道这些事实:

在任何情况下,都不能修改标识列,因此必须删除该行并重新添加新的标识。 不能从列中删除标识属性(必须删除到列) .net中的自定义命令构建器总是跳过标识列,因此不能将其用于此目的。

一旦知道了这个,你要做的就是。要么编写自己的SQL Insert语句,要么编写自己的Insert命令构建器。或者用我为你设计的这个。给定一个数据表,生成SQL插入脚本:

public static string BuildInsertSQLText ( DataTable table )
{
    StringBuilder sql = new StringBuilder(1000,5000000);
    StringBuilder values = new StringBuilder ( "VALUES (" );
    bool bFirst = true;
    bool bIdentity = false;
    string identityType = null;

    foreach(DataRow myRow in table.Rows) 
    {
        sql.Append( "\r\nINSERT INTO " + table.TableName + " (" );

        foreach ( DataColumn column in table.Columns )
        {
            if ( column.AutoIncrement )
            {
                bIdentity = true;

                switch ( column.DataType.Name )
                {
                    case "Int16":
                        identityType = "smallint";
                        break;
                    case "SByte":
                        identityType = "tinyint";
                        break;
                    case "Int64":
                        identityType = "bigint";
                        break;
                    case "Decimal":
                        identityType = "decimal";
                        break;
                    default:
                        identityType = "int";
                        break;
                }
            }
            else
            {
                if ( bFirst )
                    bFirst = false;
                else
                {
                    sql.Append ( ", " );
                    values.Append ( ", " );
                }
                sql.Append ("[");
                sql.Append ( column.ColumnName );
                sql.Append ("]");

                //values.Append (myRow[column.ColumnName].ToString() );

                if (myRow[column.ColumnName].ToString() == "True")
                    values.Append("1");
                else if (myRow[column.ColumnName].ToString() == "False")
                    values.Append("0");
                else if(myRow[column.ColumnName] == System.DBNull.Value)    
                    values.Append ("NULL");
                else if(column.DataType.ToString().Equals("System.String"))
                {
                    values.Append("'"+myRow[column.ColumnName].ToString()+"'");
                }
                else
                    values.Append (myRow[column.ColumnName].ToString());
                    //values.Append (column.DataType.ToString() );
            }
        }
        sql.Append ( ") " );
        sql.Append ( values.ToString () );
        sql.Append ( ")" );

        if ( bIdentity )
        {
            sql.Append ( "; SELECT CAST(scope_identity() AS " );
            sql.Append ( identityType );
            sql.Append ( ")" );
        }
        bFirst = true;
        sql.Append(";");
        values = new StringBuilder ( "VALUES (" );
    } //fin foreach
    return sql.ToString ();
}

我做了以下事情:

将相关数据移动到临时存储中 更新主键/标识列值(删除和创建约束) 用新的外键值重新插入相关数据

我把我的解决方案包装在一个存储过程中:

CREATE PROCEDURE [dbo].[UpdateCustomerLocationId]
    @oldCustomerLocationId INT,
    @newCustomerLocationId INT
AS
  /* 
    Updates CustomerLocation.CustomerLocationId @oldCustomerLocationId to @newCustomerLocationId
    
    Example:
        EXEC [dbo].[UpdateCustomerLocationId] 
            @oldCustomerLocationId = 6154874, 
            @newCustomerLocationId = 50334;
    */

BEGIN

    SET NOCOUNT ON;
    
    -- exit if @oldCustomerLocationId does not exists
    IF NOT EXISTS (SELECT * FROM dbo.CustomerLocation cl WHERE cl.CustomerLocationId = @oldCustomerLocationId)
    BEGIN
        PRINT CONCAT('CustomerLocationId ''', @oldCustomerLocationId, ''' (@oldCustomerLocationId) does not exist in dbo.CustomerLocation');
        RETURN 1; -- 0 = success, > 0 = failure
    END

    -- exit if @newCustomerLocationId already exists
    IF EXISTS (SELECT * FROM dbo.CustomerLocation cl WHERE cl.CustomerLocationId = @newCustomerLocationId)
    BEGIN
        PRINT CONCAT('CustomerLocationId ''', @newCustomerLocationId, ''' (@newCustomerLocationId) already exists in dbo.CustomerLocation');
        RETURN 2; -- 0 = success, > 0 = failure
    END
    

    BEGIN TRAN;


        BEGIN -- MOVE related data into temporary storage

            IF EXISTS (SELECT * FROM dbo.CustomerLocationData t WHERE t.CustomerLocationId = @oldCustomerLocationId) BEGIN
    
                IF OBJECT_ID('tempdb..#CustomerLocationData') IS NOT NULL
                    DROP TABLE #CustomerLocationData;

                SELECT * INTO #CustomerLocationData FROM dbo.CustomerLocationData t WHERE t.CustomerLocationId = @oldCustomerLocationId;
                DELETE t FROM dbo.CustomerLocationData t WHERE t.CustomerLocationId = @oldCustomerLocationId;

            END

        END


        BEGIN -- UPDATE dbo.CustomerLocation

            -- DROP CONSTRAINTs
            ALTER TABLE [dbo].[CustomerLocation] DROP CONSTRAINT [UC_CustomerLocation];

            -- INSERT OLD record with new CustomerLocationId
            SET IDENTITY_INSERT dbo.CustomerLocation ON;

            INSERT INTO dbo.CustomerLocation
            (
                CustomerLocationId, CustomerId, LocationId, CustomerLocationIdent, CustomerLocationIdent2, LocationIdent, LocationName, CustomerDistrictId, 
                CustomerLocationGUID, UpdatedOn, IssueManager, EnrollSelfMonitoring, TemperatureControlDeadlineHour, CreatedOn, OperationBegin, ActiveCustomer, 
                Comments, LocationName2, ParentGroup, TempString1, TempString2, TempString3, TempString4, TempString5, AutoInheritFromLocation, ClassificationPrimary
            )
            SELECT @newCustomerLocationId AS CustomerLocationId, CustomerId,LocationId, CustomerLocationIdent, CustomerLocationIdent2, LocationIdent, LocationName, CustomerDistrictId,
                CustomerLocationGUID, UpdatedOn, IssueManager, EnrollSelfMonitoring, TemperatureControlDeadlineHour, CreatedOn, OperationBegin, ActiveCustomer,
                Comments,LocationName2, ParentGroup, TempString1, TempString2, TempString3, TempString4, TempString5, AutoInheritFromLocation, ClassificationPrimary
            FROM dbo.CustomerLocation 
            WHERE CustomerLocationId = @oldCustomerLocationId;

            SET IDENTITY_INSERT dbo.CustomerLocation OFF;

            -- DELETE OLD record
            DELETE cl FROM dbo.CustomerLocation cl WHERE cl.CustomerLocationId = @oldCustomerLocationId;

            -- ADD CONSTRAINTS
            ALTER TABLE [dbo].[CustomerLocation] ADD CONSTRAINT [UC_CustomerLocation] UNIQUE NONCLUSTERED ([CustomerId], [LocationId]);

        END


        BEGIN -- re-INSERT related data from temporary storage

            IF OBJECT_ID('tempdb..#CustomerLocationData') IS NOT NULL BEGIN
                SET IDENTITY_INSERT dbo.CustomerLocationData ON;
                INSERT INTO dbo.CustomerLocationData (Guid, CustomerLocationId, CustomerLocationDataTypeId, Date, Category, Data)
                SELECT Guid, @newCustomerLocationId CustomerLocationId, CustomerLocationDataTypeId, Date, Category, Data FROM #CustomerLocationData;
                SET IDENTITY_INSERT dbo.CustomerLocationData OFF;
            END

        END


    COMMIT TRAN;

END