Sybase: hide timestamp columns since they're inherently read-only. Closes #7716.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6349 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

 *SVN*
 
+* Sybase: hide timestamp columns since they're inherently read-only.  #7716 [Mike Joyce]
+
 * Oracle: overflow Time to DateTime.  #7718 [Michael Schoen]
 
 * PostgreSQL: don't use async_exec and async_query with postgres-pr.  #7727 [flowdelic]

activerecord/lib/active_record/connection_adapters/sybase_adapter.rb

@@ -242,8 +242,8 @@ def columns(table_name, name = nil)
 SELECT col.name AS name, type.name AS type, col.prec, col.scale,
   col.length, col.status, obj.sysstat2, def.text
  FROM sysobjects obj, syscolumns col, systypes type, syscomments def
- WHERE obj.id = col.id AND col.usertype = type.usertype AND col.cdefault *= def.id
-  AND obj.type = 'U' AND obj.name = '#{table_name}' ORDER BY col.colid
+ WHERE obj.id = col.id AND col.usertype = type.usertype AND type.name != 'timestamp' 
+  AND col.cdefault *= def.id AND obj.type = 'U' AND obj.name = '#{table_name}' ORDER BY col.colid
 SQLTEXT
         @logger.debug "Get Column Info for table '#{table_name}'" if @logger
         @connection.set_rowcount(0)