apply Emil Kroymann's patch for Issue 75

migrate/changeset/databases/mysql.py

@@ -4,6 +4,7 @@
 
 from migrate.changeset import ansisql, exceptions, SQLA_06
 from sqlalchemy.databases import mysql as sa_base
+from sqlalchemy import types as sqltypes
 
 if not SQLA_06:
     MySQLSchemaGenerator = sa_base.MySQLSchemaGenerator
@@ -23,6 +24,14 @@ class MySQLSchemaChanger(MySQLSchemaGenerator, ansisql.ANSISchemaChanger):
     def visit_column(self, delta):
         table = delta.table
         colspec = self.get_column_specification(delta.result_column)
+        if delta.result_column.autoincrement:
+            first = [c for c in table.primary_key.columns
+                       if (c.autoincrement and
+                            isinstance(c.type, sqltypes.Integer) and
+                            not c.foreign_keys)].pop(0)
+
+            if first.name == delta.current_name:
+                colspec += " AUTO_INCREMENT"
         old_col_name = self.preparer.quote(delta.current_name, table.quote)
 
         self.start_alter_table(table)

migrate/changeset/schema.py

@@ -177,7 +177,7 @@ class ColumnDelta(DictMixin, sqlalchemy.schema.SchemaItem):
 
     # Column attributes that can be altered
     diff_keys = ('name', 'type', 'primary_key', 'nullable',
-        'server_onupdate', 'server_default')
+        'server_onupdate', 'server_default', 'autoincrement')
     diffs = dict()
     __visit_name__ = 'column'