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?
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?
您不能更新标识列。 SQL Server不允许更新标识列,这与使用更新语句更新其他列不同。
尽管有一些替代方案可以实现类似的需求。
当需要为新记录更新标识列值时
使用DBCC CHECKIDENT检查表的当前标识值,如果需要,则更改标识值。
DBCC CHECKIDENT('tableName', RESEED, NEW_RESEED_VALUE)
当需要更新现有记录的标识列值时
使用IDENTITY_INSERT,它允许显式的值插入到表的标识列中。
SET IDENTITY_INSERT YourTable {ON|OFF}
例子:
-- Set Identity insert on so that value can be inserted into this column
SET IDENTITY_INSERT YourTable ON
GO
-- Insert the record which you want to update with new value in the identity column
INSERT INTO YourTable(IdentityCol, otherCol) VALUES(13,'myValue')
GO
-- Delete the old row of which you have inserted a copy (above) (make sure about FK's)
DELETE FROM YourTable WHERE ID=3
GO
--Now set the idenetity_insert OFF to back to the previous track
SET IDENTITY_INSERT YourTable OFF
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
你需要
set identity_insert YourTable ON
然后删除行并重新插入不同的标识。
插入完成后,不要忘记关闭identity_insert
set identity_insert YourTable OFF
DBCC CHECKIDENT(table_name, RESEED, value)
Table_name =给出要重置的表的值
Value =初始值为0,以1开始单位列
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 ();
}
我已经解决了这个问题,首先使用DBCC,然后使用插入。例如,如果你的桌子是
首先在表中设置新的当前ID Value为NEW_RESEED_VALUE
MyTable { IDCol, 可乐, colB }
DBCC CHECKIDENT('MyTable', RESEED, NEW_RESEED_VALUE)
然后你可以使用
insert into MyTable (colA, ColB) select colA, colB from MyTable
这将复制所有记录,但使用新的IDCol值作为NEW_RESEED_VALUE开始。然后,在删除/移动外键引用(如果有)后,可以删除ID值较高的重复行。
将您的表复制到没有标识列的新表。
select columns into newtable from yourtable
用new seed添加一个标识列到newtable,并将其作为主键
ALTER TABLE tableName ADD id MEDIUMINT NOT NULL AUTO_INCREMENT KEY
--before running this make sure Foreign key constraints have been removed that reference the ID.
--set table to allow identity to be inserted
SET IDENTITY_INSERT yourTable ON;
GO
--insert everything into a temp table
SELECT *
INTO #tmpYourTable
FROM yourTable
--clear your table
DELETE FROM yourTable
--insert back all the values with the updated ID column
INSERT INTO yourTable (IDCol, OtherCols)
SELECT ID+1 as updatedID --put any other update logic to the ID here
, OtherCols FROM #tmpYourTable
--drop the temp table
DROP TABLE #tmpYourTable
--put identity back to normal
SET IDENTITY_INSERT yourTable OFF;
GO
您可以使用以下代码创建一个新表。
SELECT IDENTITY (int, 1, 1) AS id, column1, column2
INTO dbo.NewTable
FROM dbo.OldTable
然后删除旧的db,并将新db重命名为旧db的名称。注意:columnn1和column2表示旧表中希望保留在新表中的所有列。
ALTER TABLE tablename add newcolumn int
update tablename set newcolumn=existingcolumnname
ALTER TABLE tablename DROP COLUMN existingcolumnname;
EXEC sp_RENAME 'tablename.oldcolumn' , 'newcolumnname', 'COLUMN'
update tablename set newcolumnname=value where condition
然而,上面的代码只有在没有主-外键关系的情况下才能工作
SET IDENTITY_INSERT dbo.TableName ON
INSERT INTO dbo.TableName
(
TableId, ColumnName1, ColumnName2, ColumnName3
)
VALUES
(
TableId_Value, ColumnName1_Value, ColumnName2_Value, ColumnName3_Value
)
SET IDENTITY_INSERT dbo.TableName OFF
当使用Identity_Insert时,不要忘记包含列名,因为sql不允许你在没有指定列名的情况下进行插入
如果您特别需要将主键值更改为不同的数字(例如123 -> 1123)。identity属性阻止更改PK值。Set Identity_insert将不起作用。如果您有级联删除,则不建议执行插入/删除操作(除非您关闭了引用完整性检查)。
编辑:新版本的SQL不允许更改syscolumns实体,因此我的部分解决方案必须以艰难的方式完成。关于如何从主键中删除Identity,请参考这个SO: 从表中的列中删除Identity 这个脚本将在PK中关闭标识:
***********************
sp_configure 'allow update', 1
go
reconfigure with override
go
update syscolumns set colstat = 0 --turn off bit 1 which indicates identity column
where id = object_id('table_name') and name = 'column_name'
go
exec sp_configure 'allow update', 0
go
reconfigure with override
go
***********************
接下来,您可以设置关系,以便它们更新外键引用。否则你需要关闭关系强制执行。这个SO链接展示了如何: 如何使用T-SQL临时禁用外键约束?
现在,您可以进行更新。我写了一个简短的脚本来基于相同的列名编写所有的更新SQL(在我的情况下,我需要将CaseID增加1,000,000:
select
'update ['+c.table_name+'] SET ['+Column_Name+']=['+Column_Name+']+1000000'
from Information_Schema.Columns as c
JOIN Information_Schema.Tables as t ON t.table_Name=c.table_name and t.Table_Schema=c.table_schema and t.table_type='BASE TABLE'
where Column_Name like 'CaseID' order by Ordinal_position
最后,重新启用引用完整性,然后重新启用主键上的Identity列。
注意:我看到有些人在这些问题上问为什么。在我的例子中,我必须将来自第二个生产实例的数据合并到主DB中,这样才能关闭第二个实例。我只需要所有操作数据的PK/ fk不发生冲突。元数据fk是相同的。
我有类似的问题,我需要更新一些id,我所做的是(我需要增加他们10k):
set identity_insert YourTable ON
INSERT INTO YourTable
([ID]
,[something1]
,[something2]
,[something3])
SELECT
([ID] + 10000)
,[something1]
,[something2]
,[something3])
FROM YourTable
WHERE something1 = 'needs updeted id'
AND something2 = 'some other condition'
set identity_insert YourTable OFF
DELETE FROM YourTable
WHERE ID >= 'your old ID From'
AND ID <= 'Your old ID To'
就是这样。希望你能理解这个逻辑,在我的情况下,还有PK-FK键与其他表连接,这意味着我必须更新它们,在我可以从“YourTable”原始行删除之前。
我知道这个问题已经有答案了,我只是想以SQL查询为例,
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
这发生在我身上,因为我做了一个合并,它更新了我正在进行合并的ID。
失败的例子(注意ClownID):
MERGE ArchitectMain.dbo.BackendClowns AS TGT
USING (
SELECT ClownID
,ClownName
,Description
,Active
,EmailSubject
,AddedBy
,Added
FROM #temptable1
) AS SRC(ClownID, ClownName, Description, Active, EmailSubject, AddedBy, Added)
ON (TGT.ClownID = SRC.ClownID)
WHEN MATCHED
THEN
UPDATE
SET ClownID = SRC.ClownID
,ClownName = SRC.ClownName
,Description = SRC.Description
,Active = SRC.Active
,EmailSubject = SRC.EmailSubject
,AddedBy = SRC.AddedBy
,Added = SRC.Added;
示例(注意ClownID):
MERGE ArchitectMain.dbo.BackendClowns AS TGT
USING (
SELECT ClownID
,ClownName
,Description
,Active
,EmailSubject
,AddedBy
,Added
FROM #temptable1
) AS SRC(ClownID, ClownName, Description, Active, EmailSubject, AddedBy, Added)
ON (TGT.ClownID = SRC.ClownID)
WHEN MATCHED
THEN
UPDATE
SET ClownName = SRC.ClownName
,Description = SRC.Description
,Active = SRC.Active
,EmailSubject = SRC.EmailSubject
,AddedBy = SRC.AddedBy
,Added = SRC.Added;
就我所见,有几种方法可以做到这一点。,但在我看来最好和最快的方法是以下一种:
标识列有一个计数器,它不一定与已注册的列相同,您可以使用以下SQL命令查看该计数器的值:
DBCC CHECKIDENT('tableName', NORESEED);
然后,如果你想编辑标识列,你将不能,但我建议在重新播种计数器到你需要的数字后,做一个新的寄存器。要重新播种计数器,使用以下命令:
DBCC CHECKIDENT('tableName', RESEED, desiredNumber);
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