* out_table_col: sql_gen.Col|str

        * in_table_col: sql_gen.Col Wrap literal values in a sql_gen.NamedCol

    @param into The table to contain the output and input pkeys.

    @param default The *output* column to use as the pkey for missing rows.

        If this output column does not exist in the mapping, uses None.

    @param is_func Whether out_table is the name of a SQL function, not a table

    if into == None:

        into = out_table.name

        if is_func: into += '()'

    into = sql_gen.as_Table(into)

    def log_debug(msg): db.log_debug(msg, level=1.5)

    log_debug('Joining together input tables into temp table')

    # Place in new table for speed and so don't modify input if values edited

    flatten_cols = filter(sql_gen.is_table_col, mapping.values())

    mapping = dicts.join(mapping, flatten(db, in_table, input_joins,

        flatten_cols, preserve=[in_pkey_col], start=0))

    # Do inserts and selects

    join_cols = sql_gen.ColDict()

    while True:

        if limit_ref[0] == 0: # special case

            log_debug('Creating an empty pkeys table')