Pandas Inner Merge/join Returning All Rows

I'm trying to merge two data frames based on a column present in both, keeping only the intersection of the two sets. The desired result is: foo bar foobar x

Solution 1:

Usually it means that you have duplicates in the column(s) used for joining, resulting in cartesian product.

Demo:

In[35]: fooOut[35]:
   xyz0a121b342c563d78In[36]: barOut[36]:
   xji0a901b902a903a904b90In[37]: pd.merge(foo, bar)
Out[37]:
   xyzji0a12901a12902a12903b34904b3490