magic-removal: Merged to [2350]

git-svn-id: http://code.djangoproject.com/svn/django/branches/magic-removal@2351 bcc190cf-cafb-0310-a4f2-bffc1f526a37

AUTHORS

@@ -51,6 +51,7 @@ answer newbie questions, and generally made Django that much better:
     deric@monowerks.com
     Jeremy Dunck <http://dunck.us/>
     Clint Ecker
+    gandalf@owca.info
     Baishampayan Ghose
     Espen Grindhaug <http://grindhaug.org/>
     Gustavo Picon

django/core/management.py

@@ -752,7 +752,7 @@ def inspectdb(db_name):
     yield "# This is an auto-generated Django model module."
     yield "# You'll have to do the following manually to clean this up:"
     yield "#     * Rearrange models' order"
-    yield "#     * Add primary_key=True to one field in each model."
+    yield "#     * Make sure each model has one field with primary_key=True"
     yield "# Feel free to rename the models, but don't rename db_table values or field names."
     yield "#"
     yield "# Also note: You'll have to insert the output of 'django-admin.py sqlinitialdata [appname]'"
@@ -766,23 +766,27 @@ def inspectdb(db_name):
             relations = introspection_module.get_relations(cursor, table_name)
         except NotImplementedError:
             relations = {}
+        try:
+            indexes = introspection_module.get_indexes(cursor, table_name)
+        except NotImplementedError:
+            indexes = {}
         for i, row in enumerate(introspection_module.get_table_description(cursor, table_name)):
-            column_name = row[0]
+            att_name = row[0]
             comment_notes = [] # Holds Field notes, to be displayed in a Python comment.
             extra_params = {}  # Holds Field parameters such as 'db_column'.
 
-            if keyword.iskeyword(column_name):
+            if keyword.iskeyword(att_name):
-                extra_params['db_column'] = column_name
+                extra_params['db_column'] = att_name
-                column_name += '_field'
+                att_name += '_field'
                 comment_notes.append('Field renamed because it was a Python reserved word.')
 
             if relations.has_key(i):
                 rel_to = relations[i][1] == table_name and "'self'" or table2model(relations[i][1])
                 field_type = 'ForeignKey(%s' % rel_to
-                if column_name.endswith('_id'):
+                if att_name.endswith('_id'):
-                    column_name = column_name[:-3]
+                    att_name = att_name[:-3]
                 else:
-                    extra_params['db_column'] = column_name
+                    extra_params['db_column'] = att_name
             else:
                 try:
                     field_type = introspection_module.DATA_TYPES_REVERSE[row[1]]
@@ -797,13 +801,26 @@ def inspectdb(db_name):
                     field_type, new_params = field_type
                     extra_params.update(new_params)
 
+                # Add maxlength for all CharFields.
                 if field_type == 'CharField' and row[3]:
                     extra_params['maxlength'] = row[3]
 
+                # Add primary_key and unique, if necessary.
+                column_name = extra_params.get('db_column', att_name)
+                if column_name in indexes:
+                    if indexes[column_name]['primary_key']:
+                        extra_params['primary_key'] = True
+                    elif indexes[column_name]['unique']:
+                        extra_params['unique'] = True
+
                 field_type += '('
 
+            # Don't output 'id = meta.AutoField(primary_key=True)', because
+            # that's assumed if it doesn't exist.
+            if att_name == 'id' and field_type == 'AutoField(' and extra_params == {'primary_key': True}:
+                continue
 
-            field_desc = '%s = models.%s' % (column_name, field_type)
+            field_desc = '%s = models.%s' % (att_name, field_type)
             if extra_params:
                 if not field_desc.endswith('('):
                     field_desc += ', '

django/db/backends/ado_mssql/introspection.py

@@ -7,4 +7,7 @@ def get_table_description(cursor, table_name):
 def get_relations(cursor, table_name):
     raise NotImplementedError
 
+def get_indexes(cursor, table_name):
+    raise NotImplementedError
+
 DATA_TYPES_REVERSE = {}

django/db/backends/dummy/introspection.py

@@ -3,5 +3,6 @@ from django.db.backends.dummy.base import complain
 get_table_list = complain
 get_table_description = complain
 get_relations = complain
+get_indexes = complain
 
 DATA_TYPES_REVERSE = {}

django/db/backends/mysql/introspection.py

@@ -14,6 +14,19 @@ def get_table_description(cursor, table_name):
 def get_relations(cursor, table_name):
     raise NotImplementedError
 
+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}
+    """
+    cursor.execute("SHOW INDEX FROM %s" % quote_name(table_name))
+    indexes = {}
+    for row in cursor.fetchall():
+        indexes[row[4]] = {'primary_key': (row[2] == 'PRIMARY'), 'unique': not bool(row[1])}
+    return indexes
+
 DATA_TYPES_REVERSE = {
     FIELD_TYPE.BLOB: 'TextField',
     FIELD_TYPE.CHAR: 'CharField',

django/db/backends/postgresql/introspection.py

@@ -37,6 +37,36 @@ def get_relations(cursor, table_name):
             continue
     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}
+    """
+    # Get the table description because we only have the column indexes, and we
+    # need the column names.
+    desc = get_table_description(cursor, table_name)
+    # This query retrieves each index on the given table.
+    cursor.execute("""
+        SELECT idx.indkey, idx.indisunique, idx.indisprimary
+        FROM pg_catalog.pg_class c, pg_catalog.pg_class c2,
+            pg_catalog.pg_index idx
+        WHERE c.oid = idx.indrelid
+            AND idx.indexrelid = c2.oid
+            AND c.relname = %s""", [table_name])
+    indexes = {}
+    for row in cursor.fetchall():
+        # row[0] (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[0]:
+            continue
+        col_name = desc[int(row[0])-1][0]
+        indexes[col_name] = {'primary_key': row[2], 'unique': row[1]}
+    return indexes
+
 # Maps type codes to Django Field types.
 DATA_TYPES_REVERSE = {
     16: 'BooleanField',

django/db/backends/sqlite3/introspection.py

@@ -11,6 +11,9 @@ def get_table_description(cursor, table_name):
 def get_relations(cursor, table_name):
     raise NotImplementedError
 
+def get_indexes(cursor, table_name):
+    raise NotImplementedError
+
 # Maps SQL types to Django Field types. Some of the SQL types have multiple
 # entries here because SQLite allows for anything and doesn't normalize the
 # field type; it uses whatever was given.

docs/django-admin.txt

@@ -112,12 +112,13 @@ output:
 
 This feature is meant as a shortcut, not as definitive model generation. After
 you run it, you'll want to look over the generated models yourself to make
-customizations. In particular, you'll need to do this:
+customizations. In particular, you'll need to rearrange models' order, so that
+models that refer to other models are ordered properly.
 
-    * Rearrange models' order, so that models that refer to other models are
+If you're using Django 0.90 or 0.91, you'll need to add ``primary_key=True`` to
-      ordered properly.
+one field in each model. In the Django development version, primary keys are
-    * Add ``primary_key=True`` to one field in each model. The ``inspectdb``
+automatically introspected for PostgreSQL and MySQL, and Django puts in the
-      doesn't yet introspect primary keys.
+``primary_key=True`` where needed.
 
 ``inspectdb`` works with PostgreSQL, MySQL and SQLite. Foreign-key detection
 only works in PostgreSQL.