Python and related tables

WesKing

Hi Everyone,
I'm relatively new using Python and I can't seem to find any good information on what I'm attempting to do.  Thanks in advance if you have any tips.

Set up:
I have 3 tables; A (spatial) B (non-spatial) and C (non-spatial).  A is related to B and B is related to C.  All are in a file geodatabase and relationship classes have been built.  I would like to select features from A and traverse through B and ultimately work with the data in C.  In ArcMap I would select features in A, open related table B, then open related table C...and do what I need to do.  I would smile, pat myself on the back and go to sleep feeling satisfied 🙂  But I want to do this using Python and can't seem to figure out how, other than creating a list using a search cursor to store the unique values in A then using that list and another search cursor on B to create another list, and then do the same on C.  It seems there must be a more efficient way to do this in Python.

Thanks,
Wes

ChrisSnyder

Would this "auto-relate" take place via the ArcMap (like you would want a button or script tool to select the records in table C, per your selected features in Feature class A), or in a stand alone script?

Either way, this is very doable in Python using some search cursors... It might look something like:

fc = r"C:\temp\test.gdb\my_fc"
fieldValueListA = [r[0] for r in arcpy.da.SearchCursor(fc, ["FIELD_A"])]
tblB = r"C:\temp\test.gdb\tbl_b"
fieldValueListB = [r[0] for r in arcpy.da.SearchCursor(tblB, ["FIELD_B"], "FIELD_A in (" + str(fieldValueListA)[1:-1] + ")")]
#....and so on