Ticket #9253: 9253-consistent_short_constraint_names.diff

django/db/backends/creation.py

@@ -1 +1 @@
 import sys
 import time
+from django.utils.hashcompat import md5_constructor
 try:
     set
 except NameError:
@@ -126 +127 @@
                 r_col = f.column
                 table = opts.db_table
                 col = opts.get_field(f.rel.field_name).column
-                # For MySQL, r_name must be unique in the first 64 characters.
+                # For MySQL, r_name must be unique in the first 64 characters
+                # and Oracle identifier lengths have a limit of 30 characters.
                 # So we are careful with character usage here.
-                r_name = '%s_refs_%s_%x' % (r_col, col, abs(hash((r_table, table))))
+                r_name = '%s_refs_%s_%s' % (r_col, col,
+                        md5_constructor(r_table + table).hexdigest()[:8])
                 final_output.append(style.SQL_KEYWORD('ALTER TABLE') + ' %s ADD CONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s (%s)%s;' % \
                     (qn(r_table), qn(truncate_name(r_name, self.connection.ops.max_name_length())),
                     qn(r_col), qn(table), qn(col),
@@ -187 +190 @@
             output.append('\n'.join(table_output))
 
             for r_table, r_col, table, col in deferred:
-                r_name = '%s_refs_%s_%x' % (r_col, col,
-                        abs(hash((r_table, table))))
+                r_name = '%s_refs_%s_%s' % (r_col, col,
+                        md5_constructor(r_table + table).hexdigest()[:8])
                 output.append(style.SQL_KEYWORD('ALTER TABLE') + ' %s ADD CONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s (%s)%s;' %
                 (qn(r_table),
                 qn(truncate_name(r_name, self.connection.ops.max_name_length())),
@@ -289 +292 @@
             col = f.column
             r_table = model._meta.db_table
             r_col = model._meta.get_field(f.rel.field_name).column
-            r_name = '%s_refs_%s_%x' % (col, r_col, abs(hash((table, r_table))))
+            r_name = '%s_refs_%s_%x' % (col, r_col,
+                    md5_constructor(table + r_table).hexdigest()[:8])
             output.append('%s %s %s %s;' % \
                 (style.SQL_KEYWORD('ALTER TABLE'),
                 style.SQL_TABLE(qn(table)),