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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Formatting Data By Using CHARINDEX And SUBSTRING

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Let's say you have names stored in the format [XYZ, ABC] but would like it to be [ABC XYZ]
How do you accomplish that in SQL?
SQL provides 2 useful functions (CHARINDEX And SUBSTRING)
Run the code below to see how they work

CREATE TABLE Names (ID INT identity not null,NameField VARCHAR(50), ProperNameField VARCHAR(50))

INSERT INTO Names
SELECT 'XYZ, ABC',NULL
UNION ALL
SELECT 'Smith, John',NULL
UNION ALL
SELECT 'Jackson, Michael',NULL
UNION ALL
SELECT 'Gates, Bill',NULL


UPDATE Names
SET ProperNameField =SUBSTRING(NameField,CHARINDEX(',',NameField) + 2,
LEN(NameField) - CHARINDEX(',',NameField))
+ ' ' + LEFT(NameField,CHARINDEX(',',NameField)-1)


SELECT * FROM Names

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