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diff --git a/lib/python2.7/site-packages/django/db/backends/postgresql_psycopg2/introspection.py b/lib/python2.7/site-packages/django/db/backends/postgresql_psycopg2/introspection.py
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+++ b/lib/python2.7/site-packages/django/db/backends/postgresql_psycopg2/introspection.py
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+from __future__ import unicode_literals
+
+from django.db.backends import BaseDatabaseIntrospection, FieldInfo
+from django.utils.encoding import force_text
+
+
+class DatabaseIntrospection(BaseDatabaseIntrospection):
+ # Maps type codes to Django Field types.
+ data_types_reverse = {
+ 16: 'BooleanField',
+ 17: 'BinaryField',
+ 20: 'BigIntegerField',
+ 21: 'SmallIntegerField',
+ 23: 'IntegerField',
+ 25: 'TextField',
+ 700: 'FloatField',
+ 701: 'FloatField',
+ 869: 'GenericIPAddressField',
+ 1042: 'CharField', # blank-padded
+ 1043: 'CharField',
+ 1082: 'DateField',
+ 1083: 'TimeField',
+ 1114: 'DateTimeField',
+ 1184: 'DateTimeField',
+ 1266: 'TimeField',
+ 1700: 'DecimalField',
+ }
+
+ ignored_tables = []
+
+ def get_table_list(self, 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() if row[0] not in self.ignored_tables]
+
+ def get_table_description(self, cursor, table_name):
+ "Returns a description of the table, with the DB-API cursor.description interface."
+ # As cursor.description does not return reliably the nullable property,
+ # we have to query the information_schema (#7783)
+ cursor.execute("""
+ SELECT column_name, is_nullable
+ FROM information_schema.columns
+ WHERE table_name = %s""", [table_name])
+ null_map = dict(cursor.fetchall())
+ cursor.execute("SELECT * FROM %s LIMIT 1" % self.connection.ops.quote_name(table_name))
+ return [FieldInfo(*((force_text(line[0]),) + line[1:6] + (null_map[force_text(line[0])]=='YES',)))
+ for line in cursor.description]
+
+ def get_relations(self, 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():
+ # row[0] and row[1] are single-item lists, so grab the single item.
+ relations[row[0][0] - 1] = (row[1][0] - 1, row[2])
+ return relations
+
+ def get_key_columns(self, cursor, table_name):
+ key_columns = []
+ cursor.execute("""
+ SELECT kcu.column_name, ccu.table_name AS referenced_table, ccu.column_name AS referenced_column
+ FROM information_schema.constraint_column_usage ccu
+ LEFT JOIN information_schema.key_column_usage kcu
+ ON ccu.constraint_catalog = kcu.constraint_catalog
+ AND ccu.constraint_schema = kcu.constraint_schema
+ AND ccu.constraint_name = kcu.constraint_name
+ LEFT JOIN information_schema.table_constraints tc
+ ON ccu.constraint_catalog = tc.constraint_catalog
+ AND ccu.constraint_schema = tc.constraint_schema
+ AND ccu.constraint_name = tc.constraint_name
+ WHERE kcu.table_name = %s AND tc.constraint_type = 'FOREIGN KEY'""" , [table_name])
+ key_columns.extend(cursor.fetchall())
+ return key_columns
+
+ def get_indexes(self, cursor, table_name):
+ # This query retrieves each index on the given table, including the
+ # first associated field name
+ cursor.execute("""
+ SELECT attr.attname, idx.indkey, idx.indisunique, idx.indisprimary
+ FROM pg_catalog.pg_class c, pg_catalog.pg_class c2,
+ pg_catalog.pg_index idx, pg_catalog.pg_attribute attr
+ WHERE c.oid = idx.indrelid
+ AND idx.indexrelid = c2.oid
+ AND attr.attrelid = c.oid
+ AND attr.attnum = idx.indkey[0]
+ AND c.relname = %s""", [table_name])
+ indexes = {}
+ for row in cursor.fetchall():
+ # row[1] (idx.indkey) is stored in the DB as an array. It comes out as
+ # a string of space-separated integers. This designates the field
+ # indexes (1-based) of the fields that have indexes on the table.
+ # Here, we skip any indexes across multiple fields.
+ if ' ' in row[1]:
+ continue
+ indexes[row[0]] = {'primary_key': row[3], 'unique': row[2]}
+ return indexes