anchor.diff:  STDEVP:                                S T D E V P;
   SUM:                                   S U M;
   TAKE:                                  T A K E;
  +TEXTIMAGE_ON:                          T E X T I M A G E '_' O N;
   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/ms190273.aspx
  alter_table
      : ALTER TABLE table_name (SET '(' LOCK_ESCALATION '=' (AUTO | TABLE | DISABLE) ')'
                               | ADD column_def_table_constraint) ';'?
      ;
  
  // https://msdn.microsoft.com/en-us/library/ms174269.aspx
  
negative.code: 
  // https://msdn.microsoft.com/en-us/library/ms188783.aspx
  create_index
      : CREATE UNIQUE? clustered? INDEX id ON table_name_with_hint '(' column_name_list (ASC | DESC)? ')'
  	(index_options)?
  	(ON id)?
  	';'?
      ;
  
  // https://msdn.microsoft.com/en-us/library/ms187926(v=sql.120).aspx
  