如何创建新表,其结构应与另一个表相同
我试过了
CREATE TABLE dom AS SELECT * FROM dom1 WHERE 1=2
但发生了无法正常工作的错误
Answers:
尝试:
Select * Into <DestinationTableName> From <SourceTableName> Where 1 = 2
请注意,这不会复制索引,键等。
如果要复制整个结构,则需要生成表的“创建脚本”。您可以使用该脚本创建具有相同结构的新表。然后,您也可以根据需要将数据转储到新表中。
如果使用的是企业管理器,只需右键单击该表,然后选择“副本”以生成“创建脚本”。
这就是我用来克隆表结构(仅列)的方法。
SELECT TOP 0 *
INTO NewTable
FROM TableStructureIWishToClone
仅复制结构(复制所有列)
Select Top 0 * into NewTable from OldTable
仅复制结构(复制一些列)
Select Top 0 Col1,Col2,Col3,Col4,Col5 into NewTable from OldTable
复制数据结构
Select * into NewTable from OldTable
如果您已经有一个具有相同结构的表,并且只想复制数据,则使用此表
Insert into NewTable Select * from OldTable
sql-server
为该语法无效,fyi。
试试看..下面的一个复制现有表的整个结构,而不复制数据。
create table AT_QUOTE_CART as select * from QUOTE_CART where 0=1 ;
如果要复制数据,请使用以下数据:
create table AT_QUOTE_CART as select * from QUOTE_CART ;
我使用以下存储的proc复制表的架构,包括PK,索引,分区状态。它不是很快,但是似乎可以完成任务。II欢迎任何有关如何加快速度的想法:
/*
Clones a table's schema from an existing table (without data)
if target table exists, it will be dropped first.
The following schema elements are cloned:
* Structure
* Primary key
* Indexes
* Constraints
DOES NOT copy:
* Triggers
* File groups
ASSUMPTION: constraints are uniquely named with the table name, so that we dont end up with duplicate constraint names
*/
CREATE PROCEDURE [dbo].[spCloneTableStructure]
@SourceTable nvarchar(255),
@DestinationTable nvarchar(255),
@PartionField nvarchar(255),
@SourceSchema nvarchar(255) = 'dbo',
@DestinationSchema nvarchar(255) = 'dbo',
@RecreateIfExists bit = 1
AS
BEGIN
DECLARE @msg nvarchar(200), @PartionScript nvarchar(255), @sql NVARCHAR(MAX)
IF EXISTS(Select s.name As SchemaName, t.name As TableName
From sys.tables t
Inner Join sys.schemas s On t.schema_id = s.schema_id
Inner Join sys.partitions p on p.object_id = t.object_id
Where p.index_id In (0, 1) and t.name = @SourceTable
Group By s.name, t.name
Having Count(*) > 1)
SET @PartionScript = ' ON [PS_PartitionByCompanyId]([' + @PartionField + '])'
else
SET @PartionScript = ''
SET NOCOUNT ON;
BEGIN TRY
SET @msg =' CloneTable ' + @DestinationTable + ' - Step 1, Drop table if exists. Timestamp: ' + CONVERT(NVARCHAR(50),GETDATE(),108)
RAISERROR( @msg,0,1) WITH NOWAIT
--drop the table
if EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = @DestinationTable)
BEGIN
if @RecreateIfExists = 1
BEGIN
exec('DROP TABLE [' + @DestinationSchema + '].[' + @DestinationTable + ']')
END
ELSE
RETURN
END
SET @msg =' CloneTable ' + @DestinationTable + ' - Step 2, Create table. Timestamp: ' + CONVERT(NVARCHAR(50),GETDATE(),108)
RAISERROR( @msg,0,1) WITH NOWAIT
--create the table
exec('SELECT TOP (0) * INTO [' + @DestinationTable + '] FROM [' + @SourceTable + ']')
--create primary key
SET @msg =' CloneTable ' + @DestinationTable + ' - Step 3, Create primary key. Timestamp: ' + CONVERT(NVARCHAR(50),GETDATE(),108)
RAISERROR( @msg,0,1) WITH NOWAIT
DECLARE @PKSchema nvarchar(255), @PKName nvarchar(255),@count INT
SELECT TOP 1 @PKSchema = CONSTRAINT_SCHEMA, @PKName = CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE TABLE_SCHEMA = @SourceSchema AND TABLE_NAME = @SourceTable AND CONSTRAINT_TYPE = 'PRIMARY KEY'
IF NOT @PKSchema IS NULL AND NOT @PKName IS NULL
BEGIN
DECLARE @PKColumns nvarchar(MAX)
SET @PKColumns = ''
SELECT @PKColumns = @PKColumns + '[' + COLUMN_NAME + '],'
FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
where TABLE_NAME = @SourceTable and TABLE_SCHEMA = @SourceSchema AND CONSTRAINT_SCHEMA = @PKSchema AND CONSTRAINT_NAME= @PKName
ORDER BY ORDINAL_POSITION
SET @PKColumns = LEFT(@PKColumns, LEN(@PKColumns) - 1)
exec('ALTER TABLE [' + @DestinationSchema + '].[' + @DestinationTable + '] ADD CONSTRAINT [PK_' + @DestinationTable + '] PRIMARY KEY CLUSTERED (' + @PKColumns + ')' + @PartionScript);
END
--create other indexes
SET @msg =' CloneTable ' + @DestinationTable + ' - Step 4, Create Indexes. Timestamp: ' + CONVERT(NVARCHAR(50),GETDATE(),108)
RAISERROR( @msg,0,1) WITH NOWAIT
DECLARE @IndexId int, @IndexName nvarchar(255), @IsUnique bit, @IsUniqueConstraint bit, @FilterDefinition nvarchar(max), @type int
set @count=0
DECLARE indexcursor CURSOR FOR
SELECT index_id, name, is_unique, is_unique_constraint, filter_definition, type FROM sys.indexes WHERE is_primary_key = 0 and object_id = object_id('[' + @SourceSchema + '].[' + @SourceTable + ']')
OPEN indexcursor;
FETCH NEXT FROM indexcursor INTO @IndexId, @IndexName, @IsUnique, @IsUniqueConstraint, @FilterDefinition, @type
WHILE @@FETCH_STATUS = 0
BEGIN
set @count =@count +1
DECLARE @Unique nvarchar(255)
SET @Unique = CASE WHEN @IsUnique = 1 THEN ' UNIQUE ' ELSE '' END
DECLARE @KeyColumns nvarchar(max), @IncludedColumns nvarchar(max)
SET @KeyColumns = ''
SET @IncludedColumns = ''
select @KeyColumns = @KeyColumns + '[' + c.name + '] ' + CASE WHEN is_descending_key = 1 THEN 'DESC' ELSE 'ASC' END + ',' from sys.index_columns ic
inner join sys.columns c ON c.object_id = ic.object_id and c.column_id = ic.column_id
where index_id = @IndexId and ic.object_id = object_id('[' + @SourceSchema + '].[' + @SourceTable + ']') and key_ordinal > 0
order by index_column_id
select @IncludedColumns = @IncludedColumns + '[' + c.name + '],' from sys.index_columns ic
inner join sys.columns c ON c.object_id = ic.object_id and c.column_id = ic.column_id
where index_id = @IndexId and ic.object_id = object_id('[' + @SourceSchema + '].[' + @SourceTable + ']') and key_ordinal = 0
order by index_column_id
IF LEN(@KeyColumns) > 0
SET @KeyColumns = LEFT(@KeyColumns, LEN(@KeyColumns) - 1)
IF LEN(@IncludedColumns) > 0
BEGIN
SET @IncludedColumns = ' INCLUDE (' + LEFT(@IncludedColumns, LEN(@IncludedColumns) - 1) + ')'
END
IF @FilterDefinition IS NULL
SET @FilterDefinition = ''
ELSE
SET @FilterDefinition = 'WHERE ' + @FilterDefinition + ' '
SET @msg =' CloneTable ' + @DestinationTable + ' - Step 4.' + CONVERT(NVARCHAR(5),@count) + ', Create Index ' + @IndexName + '. Timestamp: ' + CONVERT(NVARCHAR(50),GETDATE(),108)
RAISERROR( @msg,0,1) WITH NOWAIT
if @type = 2
SET @sql = 'CREATE ' + @Unique + ' NONCLUSTERED INDEX [' + @IndexName + '] ON [' + @DestinationSchema + '].[' + @DestinationTable + '] (' + @KeyColumns + ')' + @IncludedColumns + @FilterDefinition + @PartionScript
ELSE
BEGIN
SET @sql = 'CREATE ' + @Unique + ' CLUSTERED INDEX [' + @IndexName + '] ON [' + @DestinationSchema + '].[' + @DestinationTable + '] (' + @KeyColumns + ')' + @IncludedColumns + @FilterDefinition + @PartionScript
END
EXEC (@sql)
FETCH NEXT FROM indexcursor INTO @IndexId, @IndexName, @IsUnique, @IsUniqueConstraint, @FilterDefinition, @type
END
CLOSE indexcursor
DEALLOCATE indexcursor
--create constraints
SET @msg =' CloneTable ' + @DestinationTable + ' - Step 5, Create constraints. Timestamp: ' + CONVERT(NVARCHAR(50),GETDATE(),108)
RAISERROR( @msg,0,1) WITH NOWAIT
DECLARE @ConstraintName nvarchar(max), @CheckClause nvarchar(max), @ColumnName NVARCHAR(255)
DECLARE const_cursor CURSOR FOR
SELECT
REPLACE(dc.name, @SourceTable, @DestinationTable),[definition], c.name
FROM sys.default_constraints dc
INNER JOIN sys.columns c ON dc.parent_object_id = c.object_id AND dc.parent_column_id = c.column_id
WHERE OBJECT_NAME(parent_object_id) =@SourceTable
OPEN const_cursor
FETCH NEXT FROM const_cursor INTO @ConstraintName, @CheckClause, @ColumnName
WHILE @@FETCH_STATUS = 0
BEGIN
exec('ALTER TABLE [' + @DestinationTable + '] ADD CONSTRAINT [' + @ConstraintName + '] DEFAULT ' + @CheckClause + ' FOR ' + @ColumnName)
FETCH NEXT FROM const_cursor INTO @ConstraintName, @CheckClause, @ColumnName
END;
CLOSE const_cursor
DEALLOCATE const_cursor
END TRY
BEGIN CATCH
IF (SELECT CURSOR_STATUS('global','indexcursor')) >= -1
BEGIN
DEALLOCATE indexcursor
END
IF (SELECT CURSOR_STATUS('global','const_cursor')) >= -1
BEGIN
DEALLOCATE const_cursor
END
PRINT 'Error Message: ' + ERROR_MESSAGE();
END CATCH
END
GO
CURSOR LOCAL FAST_FORWARD
。我个人试图在不使用游标的情况下创建类似的脚本,并查看其性能。
我不知道您为什么要这样做,但是请尝试:
SELECT *
INTO NewTable
FROM OldTable
WHERE 1 = 2
它应该工作。
Copy the table structure:-
select * into newtable from oldtable where 1=2;
Copy the table structure along with table data:-
select * into newtable from oldtable where 1=1;
SELECT * INTO newtable
from Oldtable
Oldtable
如果要创建具有唯一结构的表,该结构要从原始表复制,则可以使用以下命令来执行此操作。
create table <tablename> as select * from <sourcetablename> where 1>2;
通过这种错误条件,您可以保留记录并复制结构。
create table AT_QUOTE_CART as select * from QUOTE_CART where 0=1 ;
替换这些表名,我们得到:create table <tablename> as select * from <sourcetablename> where 0=1 ;
至于where子句,0=1
获得的结果与1>2
未检索到数据的结果相同。