I need to intersect two highly-overlapping shapefiles, the first with 60 polygons (ponds), the second with 3000 (lilly pads). A straight-up intersection does not work (60 x 3000 -- it runs for hours and fails. Even 1x3000 does not work). Hence, I have believe the solution to be a model with double iteration: for every pond, iterate and intersect with every lilly pad. These will be merged together at the end. Because there cannot be two iterators in a single model, I have made a main model with a nested sub-model:
Main Model- Iterate through every Lilly pad and Intersect it with EVERY pond (output from the sub-model IterateSupply2)
Sub Model (IterateSupply2) - Iterate through every pond, copy features so they can be the model parameter (and output)
This double iteration isn't working for me: instead of 60x3000, it only gives me 1x3000. I have tried various preconditions, but don't understand how they would influence a process like this.
To explain in a different way: I would like for the main model to loop through using one submodel output, before moving onto the next submodel output and looping again