anchor.diff:      ;
   
   sql_clause
  -    : dml_clause/*
  +    : dml_clause
  +
       | ddl_clause
  +
       | cfl_statement
  -    | another_statement*/
  +
  +    | another_statement
       ;
   
   // Data Manipulation Language: https://msdn.microsoft.com/en-us/library/ff848766(v=sql.120).aspx
   dml_clause
  -    : /*delete_statement
  +    : delete_statement
       | insert_statement
  -    | */select_statement/*
  +    | select_statement
       | update_statement
  -    */;/*
  +    ;
   
   // Data Definition Language: https://msdn.microsoft.com/en-us/library/ff848799.aspx)
   ddl_clause
  
positive.code:     ;
  
  common_table_expression
      : expression_name=id ('(' column_name_list ')')? AS '(' select_statement ')'
      ;
  
  /*update_elem
      : (full_column_name | LOCAL_ID) ('=' | assignment_operator) expression
      | udt_column_name=id '.' method_name=id '(' expression_list ')'
      //| full_column_name '.' WRITE (expression, )
  
negative.code: 
  parameterization_option:
       PARAMETERIZATION ( SIMPLE | FORCED )
      ;
  
  /* Will visit later
  query_store_options:
      ;
  */
  
  recovery_option:
       RECOVERY ( FULL | BULK_LOGGED | SIMPLE )
       | TORN_PAGE_DETECTION on_off
       | PAGE_VERIFY ( CHECKSUM | TORN_PAGE_DETECTION | NONE )
      ;
  
  /*Will visit later
  remote_data_archive_option:
      ;
  */
  
  service_broker_option:
      ENABLE_BROKER  
      | DISABLE_BROKER  
      | NEW_BROKER  
  