1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
"""
PostgreSQL database backend for Django.
Requires psycopg 1: http://initd.org/projects/psycopg1
"""
from django.core.db import base, typecasts
import psycopg as Database
DatabaseError = Database.DatabaseError
class DatabaseWrapper:
def __init__(self):
self.connection = None
self.queries = []
def cursor(self):
from django.conf.settings import DATABASE_USER, DATABASE_NAME, DATABASE_HOST, DATABASE_PORT, DATABASE_PASSWORD, DEBUG, TIME_ZONE
if self.connection is None:
if DATABASE_NAME == '':
from django.core.exceptions import ImproperlyConfigured
raise ImproperlyConfigured, "You need to specify DATABASE_NAME in your Django settings file."
conn_string = "dbname=%s" % DATABASE_NAME
if DATABASE_USER:
conn_string = "user=%s %s" % (DATABASE_USER, conn_string)
if DATABASE_PASSWORD:
conn_string += " password=%s" % DATABASE_PASSWORD
if DATABASE_HOST:
conn_string += " host=%s" % DATABASE_HOST
if DATABASE_PORT:
conn_string += " port=%s" % DATABASE_PORT
self.connection = Database.connect(conn_string)
self.connection.set_isolation_level(1) # make transactions transparent to all cursors
cursor = self.connection.cursor()
cursor.execute("SET TIME ZONE %s", [TIME_ZONE])
if DEBUG:
return base.CursorDebugWrapper(cursor, self)
return cursor
def commit(self):
return self.connection.commit()
def rollback(self):
if self.connection:
return self.connection.rollback()
def close(self):
if self.connection is not None:
self.connection.close()
self.connection = None
def quote_name(self, name):
if name.startswith('"') and name.endswith('"'):
return name # Quoting once is enough.
return '"%s"' % name
def dictfetchone(cursor):
"Returns a row from the cursor as a dict"
return cursor.dictfetchone()
def dictfetchmany(cursor, number):
"Returns a certain number of rows from a cursor as a dict"
return cursor.dictfetchmany(number)
def dictfetchall(cursor):
"Returns all rows from a cursor as a dict"
return cursor.dictfetchall()
def get_last_insert_id(cursor, table_name, pk_name):
cursor.execute("SELECT CURRVAL('%s_%s_seq')" % (table_name, pk_name))
return cursor.fetchone()[0]
def get_date_extract_sql(lookup_type, table_name):
# lookup_type is 'year', 'month', 'day'
# http://www.postgresql.org/docs/8.0/static/functions-datetime.html#FUNCTIONS-DATETIME-EXTRACT
return "EXTRACT('%s' FROM %s)" % (lookup_type, table_name)
def get_date_trunc_sql(lookup_type, field_name):
# lookup_type is 'year', 'month', 'day'
# http://www.postgresql.org/docs/8.0/static/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
return "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
def get_limit_offset_sql(limit, offset=None):
sql = "LIMIT %s" % limit
if offset and offset != 0:
sql += " OFFSET %s" % offset
return sql
def get_random_function_sql():
return "RANDOM()"
def get_table_list(cursor):
"Returns a list of table names in the current database."
cursor.execute("""
SELECT c.relname
FROM pg_catalog.pg_class c
LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('r', 'v', '')
AND n.nspname NOT IN ('pg_catalog', 'pg_toast')
AND pg_catalog.pg_table_is_visible(c.oid)""")
return [row[0] for row in cursor.fetchall()]
def get_relations(cursor, table_name):
"""
Returns a dictionary of {field_index: (field_index_other_table, other_table)}
representing all relationships to the given table. Indexes are 0-based.
"""
cursor.execute("""
SELECT con.conkey, con.confkey, c2.relname
FROM pg_constraint con, pg_class c1, pg_class c2
WHERE c1.oid = con.conrelid
AND c2.oid = con.confrelid
AND c1.relname = %s
AND con.contype = 'f'""", [table_name])
relations = {}
for row in cursor.fetchall():
try:
# row[0] and row[1] are like "{2}", so strip the curly braces.
relations[int(row[0][1:-1]) - 1] = (int(row[1][1:-1]) - 1, row[2])
except ValueError:
continue
return relations
# Register these custom typecasts, because Django expects dates/times to be
# in Python's native (standard-library) datetime/time format, whereas psycopg
# use mx.DateTime by default.
try:
Database.register_type(Database.new_type((1082,), "DATE", typecasts.typecast_date))
except AttributeError:
raise Exception, "You appear to be using psycopg version 2, which isn't supported yet, because it's still in beta. Use psycopg version 1 instead: http://initd.org/projects/psycopg1"
Database.register_type(Database.new_type((1083,1266), "TIME", typecasts.typecast_time))
Database.register_type(Database.new_type((1114,1184), "TIMESTAMP", typecasts.typecast_timestamp))
Database.register_type(Database.new_type((16,), "BOOLEAN", typecasts.typecast_boolean))
OPERATOR_MAPPING = {
'exact': '=',
'iexact': 'ILIKE',
'contains': 'LIKE',
'icontains': 'ILIKE',
'ne': '!=',
'gt': '>',
'gte': '>=',
'lt': '<',
'lte': '<=',
'startswith': 'LIKE',
'endswith': 'LIKE',
'istartswith': 'ILIKE',
'iendswith': 'ILIKE',
}
# This dictionary maps Field objects to their associated PostgreSQL column
# types, as strings. Column-type strings can contain format strings; they'll
# be interpolated against the values of Field.__dict__ before being output.
# If a column type is set to None, it won't be included in the output.
DATA_TYPES = {
'AutoField': 'serial',
'BooleanField': 'boolean',
'CharField': 'varchar(%(maxlength)s)',
'CommaSeparatedIntegerField': 'varchar(%(maxlength)s)',
'DateField': 'date',
'DateTimeField': 'timestamp with time zone',
'EmailField': 'varchar(75)',
'FileField': 'varchar(100)',
'FilePathField': 'varchar(100)',
'FloatField': 'numeric(%(max_digits)s, %(decimal_places)s)',
'ImageField': 'varchar(100)',
'IntegerField': 'integer',
'IPAddressField': 'inet',
'ManyToManyField': None,
'NullBooleanField': 'boolean',
'OneToOneField': 'integer',
'PhoneNumberField': 'varchar(20)',
'PositiveIntegerField': 'integer CHECK (%(column)s >= 0)',
'PositiveSmallIntegerField': 'smallint CHECK (%(column)s >= 0)',
'SlugField': 'varchar(50)',
'SmallIntegerField': 'smallint',
'TextField': 'text',
'TimeField': 'time',
'URLField': 'varchar(200)',
'USStateField': 'varchar(2)',
}
# Maps type codes to Django Field types.
DATA_TYPES_REVERSE = {
16: 'BooleanField',
21: 'SmallIntegerField',
23: 'IntegerField',
25: 'TextField',
869: 'IPAddressField',
1043: 'CharField',
1082: 'DateField',
1083: 'TimeField',
1114: 'DateTimeField',
1184: 'DateTimeField',
1266: 'TimeField',
1700: 'FloatField',
}
|