What is the use of a cursor in SQL Server?

Question

I want to use a database cursor; first I need to understand what its use and syntax are, and in which scenario we can use this in stored procedures? Are there different synt

Answer 1

I would argue you might want to use a cursor when you want to do comparisons of characteristics that are on different rows of the return set, or if you want to write a different output row format than a standard one in certain cases. Two examples come to mind:

1. One was in a college where each add and drop of a class had its own row in the table. It might have been bad design but you needed to compare across rows to know how many add and drop rows you had in order to determine whether the person was in the class or not. I can't think of a straight forward way to do that with only sql.

2. Another example is writing a journal total line for GL journals. You get an arbitrary number of debits and credits in your journal, you have many journals in your rowset return, and you want to write a journal total line every time you finish a journal to post it into a General Ledger. With a cursor you could tell when you left one journal and started another and have accumulators for your debits and credits and write a journal total line (or table insert) that was different than the debit/credit line.