Can you be more specific about what you're trying to do? A loop is used for anything that pipelines structures as a list. So if you query a table for a set of records that is a list of records that Pipelines will require a loop to access the data since it will treat the object as something it has to sequence. The opposite would be doing a Record Lookup where Pipelines knows that its only 1 thing and evaluates accordingly.
In your case - what is the action that you think needs to be looped through?
Honestly I am new to Pipelines and I am not sure that a loop is necessary but I have been looking at other threads and thought that a loop may resolve this issue. Essentially, I have a table that is a timeline chart for keeping track of our open projects. I have a tasks table that we are trying to pull data from to keep the timeline table up to date. We originally set up a record lookup and the pipeline is supposed to be triggered when a condition is met on the task table. Once that condition is met it is supposed to take the completed date from the task record and place it into a field on the timeline table. When structured with a lookup, it throws this error. Most of the responses I have seen when searching this error showed resolution by adding a search with a loop behind it. Thought that may be the case her but I am not sure. Either way, I am hoping that provides a bit more context!
If you're grabbing data from QB it really comes in just two flavors. The lookup record will give you only one record in response where you have to tell it exactly which RID you want and then you can have an update step that targets it. If you're doing a search - then a loop is required since QB is just interpreting it as a list and you have to loop through it whether you intend it to be 1 record or 100. So in this case since it sounds like you're searching for the record in the other table you'll be doing a loop.
