Simple Introduction to TSQL Cursors

A cursor is a tool in SQL Server that allows a user to traverse through the rows of a result set one row at a time. This can be useful for performing operations on each row of the result set individually, such as updating or deleting specific rows.

Cursors are created using the DECLARE CURSOR statement, and are associated with a SELECT statement that defines the result set. Once a cursor is declared, it can be used to retrieve the rows of the result set one at a time using the FETCH statement. The FETCH statement can be used to move the cursor to the next row in the result set, and the values of the columns in the current row can be accessed using the cursor’s fields.

There are two types of cursors in SQL Server: forward-only and scrollable. Forward-only cursors only allow the cursor to be moved forward through the result set, while scrollable cursors allow the cursor to be moved both forward and backward. Scrollable cursors also allow the cursor to be positioned at a specific row in the result set, whereas forward-only cursors always start at the beginning of the result set.

Using cursors can be a powerful way to manipulate data in SQL Server, but they should be used with care. Cursors can be slow and resource-intensive, especially on large result sets, and can potentially cause performance issues if not used correctly. It is important to consider the trade-offs and choose the right approach for the specific situation.

Here is a 5 minute training with an overview of TSQL cursors, and how to get started with your first cursor on SQL Server.

Simple Introduction to TSQL Cursors

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