In a previous article we discussed the how to set up a basic cursor. We explained that a cursor is a row-based operation that takes a given SELECT statement and breaks downs the processing of the data into looping executions. People that do not have the background in Database Administration or who did not enjoy database classes while studying will often find SQL Server cursors handy and fun to write. This is because they break free of the shackles of set-based logic that is the normal when writing most T-SQL scripts. It is for this reason that we so often find SQL Server cursors written into the business logic of an application and it is a real pity because they are real performance hogs. Yes, there are times when cursors are OK to use and they can be tuned slightly by playing with their different types but, as a general rule of thumb, one should try to avoid them at all costs.
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