[BUG] Error with outerJoin in Getting Cohort Dispatch

[TheCedarPrince]

I had seen this bug a few times and thought maybe I was just "using it wrong", but it just dawned on me that there is actually an error here as the outerjoin should also join on the :subject_id variable or else there will result duplicate column name errors.

"""
function GetCohortSubjectStartDate(df:DataFrame, conn; tab = cohort)

Given a `DataFrame` with a `:cohort_definition_id` column and `:subject_id` column, return the `DataFrame` with an associated `:cohort_start_date` corresponding to a cohort's subject ID in the `DataFrame`

Multiple dispatch that accepts all other arguments like in `GetCohortSubjectStartDate(ids, conn; tab = cohort)`
"""
function GetCohortSubjectStartDate(
    df::DataFrame, 
    conn; 
    tab = cohort
)

    return outerjoin(GetCohortSubjectStartDate(df[:,"cohort_definition_id"], df[:,"subject_id"], conn; tab=tab), df, on = :cohort_definition_id)

end

@Jay-sanjay, I am not sure how we missed this with the tests... Did we not have a test that accounted for a dataframe with both cohort_definition_id and subject_id? I guess I am just surprised we missed this; ah well!

[Jay-sanjay]

Hi, @TheCedarPrince I guess that's strange, because I think this should have done that part , right ?

OMOPCDMCohortCreator.jl/test/sqlite/getters.jl

Lines 493 to 494 in f78c77e

	test_df1 = DataFrame(cohort_definition_id = test_cohort_definition_ids, subject_id = test_subject_ids, cohort_start_date = res.cohort_start_date[1:8])

[TheCedarPrince]

Weird!!! Are you able to see the error too @Jay-sanjay ? Let me see if I can get a code example shortly so you can see what I am seeing.