Cursor And It's Life Cycle

By Freshlyne

What is Cursor in SQL Server?

Cursor can be seen as a way to implement looping to SQL , which isn't a programming language, so much so it is a transactional language.

SQL Cursor Life Cycle

The following steps are involved in a SQL cursor life cycle. 



1. Declaring Cursor

At this stage, we define the SQL statement for the cursor, in turn defining the data set on which we are supposed to loop.

2. Opening Cursor

Once we know the dataset, it's time to actually fetch that dataset for our cursor to run through.

3. Fetching Cursor

This is the main step which is being looped over, in a sense. It fetches one row at a time from our cursor so that operations can be performed on the data fetched.

4. Closing Cursor

The cursor should be closed explicitly after data manipulation.

5. Deallocating Cursor

Cursors should be deallocated to delete cursor definition and release all the system resources associated with the cursor.


In upcoming blog we will have an example on CURSOR.

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