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1.SQL Server 2008 Backup
ÌâÄ¿£ºIs it possible to restore a SQL Server 2008 Enterprise Edition compressed backup to a SQL Server 2008 Standard Edition?
´ð°¸£ºyes
½âÊÍ£ºRESTORE from compressed backups on SQL Server 2008 Standard Edition is possible, although the backup compression feature is not supported in SQL Server 2008 Standard Edition.
²Î¿¼£º±¸·ÝѹËõ (SQL Server)
2.Identity
ÌâÄ¿£ºWe want to insert record into table a
create table a (a int identity(1,1))
Which statement will work?
insert into a default values
insert into a values (default)
insert into a values (1)
could not insert explicit for identity column
´ð°¸£ºinsert into a default values
½âÊÍ£ºAn insert statement with "default values" works.
²Î¿¼£ºINSERT
3.Dynamic SQL
ÌâÄ¿£ºSam has to run a query dynamically & get the count in a variable and do some processing based on the count. Which of the following queries will return expected output?
declare @tablevariable varchar(100)
set @tablevariable = 'Employees'
A)
declare @sql varchar(100)
Declare @cnt int
Set @sql = 'Select ' + Convert(varchar(100),@cnt) + ' =count(*) from ' + @tablevariable
Exec (@sql) select @cnt
B)
declare @sql varchar(100)
Declare @cnt int
Set @sql = 'Select count(*) from ' + @tablevariable
@cnt = Exec (@sql) select @cnt
C)
DECLARE @sql nvarchar(4000), @params nvarchar(4000), @count int
SELECT @sql = N' SELECT @cnt = COUNT(*) from dbo.' + quotename(@tablevariable)
SELECT @params = N'@cnt int OUTPUT'
EXEC sp_executesql @sql, @params, @cnt = @count OUTPUT select @count
´ð°¸£ºC
½âÊÍ£ºFor getting a variable as output in a dynamic statement, we need to use sp_executeSQL.
²Î¿¼£ºIntroducing Dynamic SQL
4.T-SQL Output Clause
ÌâÄ¿£ºExecuting the