Execute Dynamic SQL commands in SQL Server

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In some applications having hard-coded SQL statements is not appealing, because of the dynamic nature of the queries being issued against the database server. Because of this sometimes there is a need to dynamically create a SQL statement on the fly and then run that command. This can be done quite simply from the application perspective where the statement is built on the fly whether you are using ASP.NET , ColdFusion or any other programming language. But how do you do this from within a SQL Server stored procedure? SQL Server offers a few ways of running a dynamically built SQL statement. These ways are: Writing a query with parameters Using EXEC Using sp_executesql Writing a query with parameters This first approach is pretty straightforward if you only need to pass parameters into the WHERE clause of your SQL statement. Let’s say we need to find all records from the Customers table where City = ‘London’. This can be done easily as the following example shows. ...
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Date formatting in SQL Server

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Declare @d datetime
select @d = getdate()

select @d as OriginalDate,
convert(varchar,@d,100) as ConvertedDate,
100 as FormatValue,
'mon dd yyyy hh:miAM (or PM)' as OutputFormat
union all
select @d,convert(varchar,@d,101),101,'mm/dd/yy'
union all
select @d,convert(varchar,@d,102),102,'yy.mm.dd'
union all
select @d,convert(varchar,@d,103),103,'dd/mm/yy'
union all
select @d,convert(varchar,@d,104),104,'dd.mm.yy'
union all
select @d,convert(varchar,@d,105),105,'dd-mm-yy'
union all
select @d,convert(varchar,@d,106),106,'dd mon yy'
union all
select @d,convert(varchar,@d,107),107,'Mon dd, yy'
union all
select @d,convert(varchar,@d,108),108,'hh:mm:ss'
union all
select @d,convert(varchar,@d,109),109,'mon dd yyyy hh:mi:ss:mmmAM (or PM)'
union all
select @d,convert(varchar,@d,110),110,'mm-dd-yy'
union all
select @d,convert(varchar,@d,111),111,'yy/mm/dd'
union all
select @d,convert(varchar,@d,112),112,'yymmdd'
union all
select @d,convert(varchar,@d,113),113,'dd mon yyyy hh:mm:ss:mmm(24h)'
union all
select @d,convert(varchar,@d,114),114,'hh:mi:ss:mmm(24h)'
union all
select @d,convert(varchar,@d,120),120,'yyyy-mm-dd hh:mi:ss(24h)'
union all
select @d,convert(varchar,@d,121),121,'yyyy-mm-dd hh:mi:ss.mmm(24h)'
union all
select @d,convert(varchar,@d,126),126,'yyyy-mm-dd Thh:mm:ss:mmm(no spaces)'

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