fetchone

fetchone is a method commonly found in database connectors and programming language libraries used to interact with databases. Its primary function is to retrieve a single row of data from a query result set. When a database query is executed, it typically returns a collection of rows. The fetchone method allows a program to access these rows one by one.

When fetchone is called, it returns the next available row from the result set. The format of the returned row can vary depending on the specific library or driver being used, but it is often a tuple or a list of values, where each value corresponds to a column in the selected row. If there are no more rows left in the result set, fetchone will usually return a special value, such as None or an empty sequence, to indicate that the end has been reached.

This method is particularly useful when a program only needs to process one record at a time, or when dealing with potentially very large result sets where loading all data into memory at once might be inefficient or impossible. Developers often use fetchone within a loop to iterate through all the rows of a query result.