Backed out [6165]. It breaks things for people using psycopg2 because…

… it requires psycopg to also be installed due to imports.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@6171 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/backends/postgresql_psycopg2/introspection.py

@@ -1,8 +1,23 @@
 from django.db.backends.postgresql_psycopg2.base import DatabaseOperations
-from django.db.backends.postgresql.introspection import get_table_list, get_table_description, get_indexes, DATA_TYPES_REVERSE
 
 quote_name = DatabaseOperations().quote_name
 
+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_table_description(cursor, table_name):
+    "Returns a description of the table, with the DB-API cursor.description interface."
+    cursor.execute("SELECT * FROM %s LIMIT 1" % quote_name(table_name))
+    return cursor.description
+
 def get_relations(cursor, table_name):
     """
     Returns a dictionary of {field_index: (field_index_other_table, other_table)}
@@ -20,3 +35,49 @@ def get_relations(cursor, table_name):
         # 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_indexes(cursor, table_name):
+    """
+    Returns a dictionary of fieldname -> infodict for the given table,
+    where each infodict is in the format:
+        {'primary_key': boolean representing whether it's the primary key,
+         'unique': boolean representing whether it's a unique index}
+    """
+    # 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
+
+# Maps type codes to Django Field types.
+DATA_TYPES_REVERSE = {
+    16: 'BooleanField',
+    21: 'SmallIntegerField',
+    23: 'IntegerField',
+    25: 'TextField',
+    701: 'FloatField',
+    869: 'IPAddressField',
+    1043: 'CharField',
+    1082: 'DateField',
+    1083: 'TimeField',
+    1114: 'DateTimeField',
+    1184: 'DateTimeField',
+    1266: 'TimeField',
+    1700: 'DecimalField',
+}