I was recently building an InfoPath form and had a number of dropdown controls that used information from SharePoint lists as their data sources.  I noticed when I previewed the form that only the first 100 items were returned to one of these dropdown controls.

 

I googled 'infopath 100 items from datasource' and quickly found this post that explains that when using a SharePoint list as a datasource, the items returned will be the items from the default view of the list that is your datasource.  This was easy enough to comprehend and so I tried to go fix my default view.

 

Now I don't know if this has anything to do with what I was experiencing, but my default view is a datasheet view.  When I went and looked at the item limit for this view, 'Display all items' was already selected.  This seemed to be a little inconsistent with the  post I had read, which is what prompted me to post my findings here.  Even though Display All Items was selected I change the # in the 'Limit Total # of Items' option to 500, and kept the first radio button checked.

 

When I saved the changes, even though visibly nothing had changed on the default view, my InfoPath form dropdown control now returned all 176 items.  Problem solved.