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pandasmergekeyerror

Keyerror on pd.merge()

I am trying to merge 2 data-frames ('credit' and 'info') on the column 'id'.

My code for this is:

c.execute('SELECT * FROM "credit"')
credit=c.fetchall()
credit=pd.DataFrame(credit)
c.execute('SELECT * FROM "info"')
info=c.fetchall()
movies_df=pd.DataFrame(info)
movies_df_merge=pd.merge(credit, movies_df, on='id')

Both of the id column types from the tables ('credit' and 'info') integers, but I am unsure of why I keep getting a key error on 'id'.

I have also tried:

movies_df_merge=movies_df.merge(credit, on='id')
Solution

  • The way how you read both DataFrames is not relevant here.

    Just print both DataFrames (if the number of records is big, it will be enough to print(head(df))).

    Then look at them. Especially check whether both DataFrames contains id column. Maybe one of them is ID, whereas another is id? The upper / lower case of names does matter here.

    Check also that id column in both DataFrames is a "normal" column (not a part of the index).