Programming Examples

Are you a Programmer or Application Developer or a DBA? Take a cup of coffee, sit back and spend few minutes here :)

SQL Server

Articles on SQL, TSQL and Management Studio. You can download Microsoft supplied sample database here: https://drive.google.com/file/d/0B8H2WLrOYbPxcy13RG9JNUpRRHM/edit?usp=sharing

Updating Table Data Via SQL Views

Joins and Calculated Columns

An SQL View is nothing but a select query with a name given to it or we can say a view is a ‘Named Query’. Why we need a view? There will be a lot of answers for this. Some important answers are below:

1) A View can bring data from many tables by using suitable joins and while bringing so, it may use complex filters and calculated data to form the needed result set. In user point of view, all these complications are hidden, and they feel that they are pulling data from a single table.
2) Some time for security reasons, access to the table and its private details like table schema and relations are not given to the DB users. All they have is access to a view without the knowledge of what tables are actually sitting in the DB.
3) Using the view, the DB admin can restrict an user to update only some portions of the records.

Continue Reading →

Ranking Functions Examples – RANK, DENSE_RANK & Percentile

SQL Dense Rank Example

Ranking Functions are useful to provide ranking on the table columns based on the value stored in it. Say, for example, let us say a table is having students id and their Total Marks as separate columns. Now, it is meaningful if we apply the these function on the Total Marks column rather than Student ID column. With these Functions, we can easily find 2nd maximum, or 4th maximum marks. The Ranking Functions are available in SQL 2005 and later versions.

Continue Reading →