anchor.diff:  STDEV:                                 S T D E V;
   STDEVP:                                S T D E V P;
   SUM:                                   S U M;
  +TAKE:                                  T A K E;
   THROW:                                 T H R O W;
   TIES:                                  T I E S;
   TIME:                                  T I M E;
  
positive.code: 
  // https://msdn.microsoft.com/en-us/library/ms187742.aspx
  column_definition
      : column_name (data_type | AS expression) (COLLATE id)? null_notnull?
        ((CONSTRAINT constraint=id)? DEFAULT constant_expression (WITH VALUES)?
         | IDENTITY ('(' seed=DECIMAL ',' increment=DECIMAL ')')? (NOT FOR REPLICATION)?)?
        ROWGUIDCOL?
  
negative.code: 
  // runtime check.
  bulk_option
      : id '=' bulk_option_value=(DECIMAL | STRING)
      ;
  
  derived_table
  