I need to filter a set of records based on a 'not equal to' (NEQ) condition. For example if I want get all products where brand is not equal to say "X". How to configure this situation in pipeline?
As mentioned in a previous answer, you can use a Record Filter, which is the Nr parameter, to accomplish this. You can read more about Record Filters in the Advanced Developer Guide.
Since the question is specifically about configuring the pipeline to support this, it is worth pointing out that you have to explicitly enable properties for Record Filter while all dimensions are automatically available for Record Filter. In most cases 'Brand' is likely to be a dimension, in which case your query will look like this:
Nr=NOT(brand:X)
It is likely you'll want to take this further to use nested filters which I suggest you look at the examples in the documentation.