Reducing stages operate on the entire set of results at once, unlike expanding stages which operate on each row individually from the previous stage's results. A good example of a reducing stage would be the
sort command, which will operate on the entire set of results from the previous stage and transform it into a sorted set of results.
How to run a reducing stage?
Certain commands in the crul query language are reducingg operations. Whenever they are used, the stage containing the command will run as a reducing stage. Generally, commands that modify data, such as the
sort command or the
table command, are reducing commands that will execute as reducing stages when run.