Python Pandas to_sql, how to create a table with a primary key?

patapouf_ai picture patapouf_ai · Jun 16, 2015 · Viewed 46.9k times · Source

I would like to create a MySQL table with Pandas' to_sql function which has a primary key (it is usually kind of good to have a primary key in a mysql table) as so:

group_export.to_sql(con = db, name = config.table_group_export, if_exists = 'replace', flavor = 'mysql', index = False)

but this creates a table without any primary key, (or even without any index).

The documentation mentions the parameter 'index_label' which combined with the 'index' parameter could be used to create an index but doesn't mention any option for primary keys.

Documentation

Answer

tomp picture tomp · Nov 23, 2016

Simply add the primary key after uploading the table with pandas.

group_export.to_sql(con=engine, name=example_table, if_exists='replace', 
                    flavor='mysql', index=False)

with engine.connect() as con:
    con.execute('ALTER TABLE `example_table` ADD PRIMARY KEY (`ID_column`);')