does the reduce stage of a map reduce script run if there is only one iteration of map?

AI generated answer (using internal Slack threads):

Yes, the reduce stage of a map reduce script will run even if there is only one iteration of map. The map stage is used to process and pass data to the reduce stage. Even if there is only one iteration in the map stage, the reduce stage will still execute to process the data passed from the map stage. However, it's important to note that if there is no data passed from the map stage to the reduce stage, the reduce stage will not execute. This is because the reduce stage is dependent on the data passed from the map stage. In a Map/Reduce script, the

summarize

stage should always run, regardless of whether there is output in the

reduce

stage or not. The

summarize

stage is designed to execute after the

map

and

reduce

stages have completed, and it provides a summary of the script's execution. In terms of script design, whether to start with

map

or

reduce

depends on the specific requirements of your script. If you know that you will need both

map

and

reduce

, then starting at

map

allows you to build the first stage first. However, if you don't need both, then using

reduce

first can work great. Remember, the

map

stage has a limit of 1K units, while the

reduce

stage has a limit of 5K units. So, if your script requires more units, you might want to consider starting with the

reduce

stage. Lastly, it's not possible to pass values straight to the

summarize

stage in a Map/Reduce script. Each step in a Map/Reduce script saves the step result to the corresponding context. If you're skipping the actual `map`/`reduce`, you might want to reconsider the type of script you're using. ****** Disclaimer: This response was generated by an artificial intelligence assistant based on previous conversations from multiple Slack channels, and may contain inaccuracies or mistakes. ******