anchor.diff:  lock_type
      : ACCESS (SHARE | EXCLUSIVE)
      | ROW (SHARE | EXCLUSIVE)
  -   | SHARE (UPDATE EXCLUSIVE | ROW EXCLUSIVE |)
  +   | SHARE (UPDATE EXCLUSIVE | ROW EXCLUSIVE)?
      | EXCLUSIVE
      ;
   
  
positive.code:    ;
  
  plsql_opt_transaction_chain
     : AND (CHAIN | NO CHAIN)
     |
     ;
  
  
negative.code: 
  func_alias_clause
     : alias_clause
     | (AS colid? | colid) OPEN_PAREN tablefuncelementlist CLOSE_PAREN
     |
     ;
  
  