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declare @str varchar(50)
declare @i int
set @str = ''
set @i=0
while @i<50
begin
set @str = @str + char(33 + cast(ceiling(rand() * 80) as int))
set @i = @i+1
end
select @str
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if OBJECT_ID('tb') is not null
drop table tb
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int OBJECT_ID('objectname');
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http://www.sql-server-performance.com/tips/clustered_indexes_p1.aspx
As a rule of thumb, every table should have a clustered index. Generally, but not always, the clustered index should be on a column that monotonically increases--such as an identity column, or some other column where the value is ......
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right(char_expr,int_expr) ·µ»Ø×Ö·û´®ÓÒ±ßint_expr¸ö×Ö·û
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upper(char_expr) תΪ´óд
lower(char_expr) תΪСд
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Load the SQL Server 2005 Driver for JDBC before you load the SQL Server 2000 Driver for JDBC. To do this, use the DriverManager class as in the following code example.
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver"); // 2005 version
Class.forName("com.microsoft.jdbc.sqlserver.SQLSe ......