tables.py 文件源码

def extract_tables(sql):
    """
    Extract the table names from an SQL statment.
    Returns a list of TableReference namedtuples.
    """
    parsed = sqlparse.parse(sql)
    if not parsed:
        return ()

    # INSERT statements must stop looking for tables at the sign of first
    # Punctuation. eg: INSERT INTO abc (col1, col2) VALUES (1, 2)
    # abc is the table name, but if we don't stop at the first lparen, then
    # we'll identify abc, col1 and col2 as table names.
    insert_stmt = parsed[0].token_first().value.lower() == 'insert'
    stream = extract_from_part(parsed[0], stop_at_punctuation=insert_stmt)

    # Kludge: sqlparse mistakenly identifies insert statements as
    # function calls due to the parenthesized column list, e.g. interprets
    # "insert into foo (bar, baz)" as a function call to foo with arguments
    # (bar, baz). So don't allow any identifiers in insert statements
    # to have is_function=True
    identifiers = extract_table_identifiers(stream,
                                            allow_functions=not insert_stmt)
    # In the case 'sche.<cursor>', we get an empty TableReference; remove that
    return tuple(i for i in identifiers if i.name)