if not create: raise

        return put(db, table, row, pkey, row_ct_ref) # insert new row

    '''Recovers from errors.

    Only works under PostgreSQL (uses INSERT RETURNING).

    @param in_tables The main input table to select from, followed by a list of

    @param mapping dict(out_table_col=in_table_col, ...)

        * out_table_col: sql_gen.Col|str

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

    @return sql_gen.Col Where the output pkeys are made available

    '''

    out_table = sql_gen.as_Table(out_table)

    for in_table_col in mapping.itervalues():

        assert isinstance(in_table_col, sql_gen.Col)

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

    log_debug('Inserting these input columns into '

        +strings.as_tt(out_table.to_str(db))+':\n'+strings.as_table(mapping))

    pkeys = sql_gen.Table(temp_prefix+'_pkeys')

    # Create input joins from list of input tables