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Which of the following ranking functions distribute the rows in an ordered partition into a specified number of groups? A. ROW_NUMBER B. RANK C. DENSE_RANK D. NTILE E. None of the Above Ans :- D Explanation:- The NTILE ranking function distributes the rows in an ordered partition into a specified number of groups. The groups are numbered, starting at one. For each row, NTILE returns the number of the group to which the row belongs. The ROW_NUMBER ranking function returns the sequential number of a row within a partition of a result set, starting at 1 for the first row in each partition. The RANK ranking function returns the rank of each row within the partition of a result set. The rank of a row is one plus the number of ranks that come before the row in question. Just like the DENSE_RANK, in the RANK ranking function, if two or more rows tie for a rank, each tied rows receive the same rank. Unlike the DENSE_RANK, the RANK ranking function does not always return con...

SELECT @@IDENTITY It returns the last IDENTITY value produced on a connection, regardless of the table that produced the value, and regardless of the scope of the statement that produced the value. @@IDENTITY will return the last identity value entered into a table in your current session. While @@IDENTITY is limited to the current session, it is not limited to the current scope. If you have a trigger on a table that causes an identity to be created in another table, you will get the identity that was created last, even if it was the trigger that created it. SELECT SCOPE_IDENTITY() It returns the last IDENTITY value produced on a connection and by a statement in the same scope, regardless of the table that produced the value. SCOPE_IDENTITY(), like @@IDENTITY, will return the last identity value created in the current session, but it will also limit it to your current scope as well. In other words, it will return the last identity value that you explicitly created, rather t...

Types of User Defined Functions There are three different types of User Defined Functions. Each type refers to the data being returned by the function. Scalar functions return a single value. In Line Table functions return a single table variable that was created by a select statement. The final UDF is a Multi-statement Table Function. This function returns a table variable whose structure was created by hand, similar to a Create Table statement. It is useful when complex data manipulation inside the function is required. Scalar UDFs Our first User Defined Function will accept a date time, and return only the date portion. Scalar functions return a value. From inside Query Analyzer, enter:   CREATE FUNCTION dbo.DateOnly(@InDateTime datetime) RETURNS varchar(10) AS BEGIN         DECLARE @MyOutput varchar(10)         SET @MyOutput = CONVERT ( varchar(10) ,@InDateTime,101)   ...

Advantages of User Defined Functions Before SQL 2000, User Defined Functions (UDFs), were not available. Stored Procedures were often used in their place. When advantages or disadvantages of User Defined Functions are discussed, the comparison is usually to Stored Procedures. One of the advantages of User Defined Functions over Stored Procedures, is the fact that a UDF can be used in a Select, Where, or Case statement. They also can be used to create joins. In addition, User Defined Functions are simpler to invoke than Stored Procedures from inside another SQL statement. Disadvantages of User Defined Functions User Defined Functions cannot be used to modify base table information. The DML statements INSERT, UPDATE, and DELETE cannot be used on base tables. Another disadvantage is that SQL functions that return non-deterministic values are not allowed to be called from inside User Defined Functions. GETDATE is an example of a non-deterministic function. Every time th...

What are the SQL Server system databases and can you outline the general functionality of each database? Master - Database responsible for SQL Server instance related data.  You can also think of this database corresponding to the Windows SQL Server service account. Resource - Database responsible for SQL Server system objects.  This database was introduced in SQL Server 2005 and is intended to ease the upgrade and rollback of SQL Server system objects. Model - Template database for the creation of new user defined databases. MSDB - Database responsible for SQL Server Agent related data such as Jobs, Alerts, Operators, etc. TempDB - Temporary database to store temporary tables (#temptable or ##temptale), table variables, cursors, work tables, row versioning, create or rebuild indexes sorted in TempDB, etc.  Each time the SQL Server instance is restarted all objects in this database are destroyed, so permanent objects cannot be created in this databa...

System Databases Do's and Don'ts Data Access - Based on the version of SQL Server query only the recommended objects.  In general the system database objects are being deprecated to a set of views, so be sure all of your scripts are accessing the right objects.  If not, you are going to have a big project in the future to convert all of your scripts. Changing Objects - Do not change system objects.  In SQL Server 2005 all of the database objects have been moved to the Resource database which stores the definition for the system objects and can be updated via new SQL Server releases independent of the data. New Objects - Creating objects in the system databases is not recommended.  If you have objects that are needed for the instance i.e. administrative items, just create a separate DBA database to store these objects. Sneaking a Peak - Up to this point, all of the T-SQL code for the tables, views, stored procedures, functions, etc. has been ...

SQL Server System Databases Master Database Purpose - Core system database to manage the SQL Server instance.  In SQL Server 2005, the Master database is the logical repository for the system objects residing in the sys schema.  In SQL Server 2000 and previous editions of SQL Server, the Master database physically stored all of the system objects. Prominent Functionality Per instance configurations Databases residing on the instance Files for each database Logins Linked\Remote servers Endpoints Additional Information The first database in the SQL Server startup process In SQL Server 2005, needs to reside in the same directory as the Resource database Sources for Database Information - SQL Server 2000 to 2005 Crosswalk SQL 2000 to 2005 Crosswalk - Startup Parameters Resource Database Purpose - The Resource database is responsible for physically storing all of the SQL Server 2005 system objects. This database has been created to impr...