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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Covert Row To Column In SQL Server 2005

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Let us suppose that you have a table like below

col1 | col2 | col3

--------*---------*----------

Value 1 | Value 2 | Value 3

And change it to one that looks like this:

Name | Value

-----*---------

col1 | Value 1

-----*---------

col2 | Value 2

-----*---------

col3 | Value 3





DECLARE @Table Table

(col1 varchar(10),

col2 varchar(10),

col3 varchar(10))

INSERT INTO @TABLE VALUES ('Value 1', 'Value 2', 'Value 3')

INSERT INTO @TABLE VALUES ('Value 4', 'Value 5', 'Value 6')

INSERT INTO @TABLE VALUES ('Value 7', 'Value 8', 'Value 9')



SELECT col, colval

FROM

(SELECT col1, col2, col3

FROM @TABLE) p

UNPIVOT

(ColVal FOR Col IN

(col1, col2, col3)

)AS unpvt

Comments

Unknown said…
Very interesting story,. I didn't find it boring to read. In fact, I really had a fun reading your post. Thanks.

Shella
www.gofastek.com
November 2, 2014 at 5:54 PM
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