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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Find all Primary and Foreign Keys In A Database

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To find all your foreign and primary keys in your database run the code below.
The ouput will return the primary key, primary key table, foreign key, foreign key table. Primary keys that don't have foreign keys will have N/A in the foreign key output

USE Northwind

SELECT tc.TABLE_NAME AS PrimaryKeyTable,
tc.CONSTRAINT_NAME AS PrimaryKey,
COALESCE(rc1.CONSTRAINT_NAME,'N/A') AS ForeignKey ,
COALESCE(tc2.TABLE_NAME,'N/A') AS ForeignKeyTable
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc
LEFT JOIN INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1 ON tc.CONSTRAINT_NAME =rc1.UNIQUE_CONSTRAINT_NAME
LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc2 ON tc2.CONSTRAINT_NAME =rc1.CONSTRAINT_NAME
WHERE TC.CONSTRAINT_TYPE ='PRIMARY KEY'
ORDER BY tc.TABLE_NAME,tc.CONSTRAINT_NAME,rc1.CONSTRAINT_NAME

Comments

Jai said…
u are not giving info about the columns referring to sir...
March 11, 2010 at 10:00 PM
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