Asked by: Camila Georgius
technology and computing databases

Which SQL command is used to iterate through each row in a cursor?

Last Updated: 4th February, 2020

In SQL Server the cursor is a tool that is used to iterate over a result set, or to loop through each row of a result set one row at a time. It may not be the best way to work with a set of data, but if you need to loop row by agonizing row (RBAR) in a T-SQL script then a cursor is one way of doing it.

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Just so, how do I run a SQL cursor?

To use cursors in SQL procedures, you need to do the following:

  1. Declare a cursor that defines a result set.
  2. Open the cursor to establish the result set.
  3. Fetch the data into local variables as needed from the cursor, one row at a time.
  4. Close the cursor when done.

Secondly, what is cursor in SQL example? Oracle creates a memory area, known as the context area, for processing an SQL statement, which contains all the information needed for processing the statement; for example, the number of rows processed, etc. A cursor is a pointer to this context area. A cursor holds the rows (one or more) returned by a SQL statement.

Secondly, which is better cursor or while loop?

Not really. In terms of what it is doing, a while loop and a cursor both do the same thing, they operate on one row at a time. A lot of people when trying to remove cursor-based code, simply replace it with a while loop, in the hope that it will run faster, because it's not a *nasty* cursor.

How do I create a cursor?

In the above syntax, the declaration part contains the declaration of the cursor and the cursor variable in which the fetched data will be assigned. The cursor is created for the 'SELECT' statement that is given in the cursor declaration. In execution part, the declared cursor is opened, fetched and closed.

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