1 import re

     2 

     3 # Valid query types (a dictionary is used for speedy lookups).

     4 QUERY_TERMS = dict([(x, None) for x in (

     5     'exact', 'iexact', 'contains', 'icontains', 'gt', 'gte', 'lt', 'lte', 'in',

     6     'startswith', 'istartswith', 'endswith', 'iendswith', 'range', 'year',

     7     'month', 'day', 'isnull', 'search', 'regex', 'iregex',

     8     )])

     9 

    10 # Size of each "chunk" for get_iterator calls.

    11 # Larger values are slightly faster at the expense of more storage space.

    12 GET_ITERATOR_CHUNK_SIZE = 100

    13 

    14 # Separator used to split filter strings apart.

    15 LOOKUP_SEP = '__'

    16 

    17 # Constants to make looking up tuple values clearer.

    18 # Join lists

    19 TABLE_NAME = 0

    20 RHS_ALIAS = 1

    21 JOIN_TYPE = 2

    22 LHS_ALIAS = 3

    23 LHS_JOIN_COL = 4

    24 RHS_JOIN_COL = 5

    25 NULLABLE = 6

    26 

    27 # How many results to expect from a cursor.execute call

    28 MULTI = 'multi'

    29 SINGLE = 'single'

    30 

    31 ORDER_PATTERN = re.compile(r'\?|[-+]?[.\w]+$')

    32 ORDER_DIR = {

    33     'ASC': ('ASC', 'DESC'),

    34     'DESC': ('DESC', 'ASC')}

    35 

    36