AlterQuery  tab (children 3)
 ExpressionList (children 1)
  AlterCommand ADD_INDEX (children 1)
   Index (children 2)
    Identifier s
    Function text (children 1)
     ExpressionList (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier tokenizer
        Function ngrams (children 1)
         ExpressionList (children 1)
          Literal UInt64_2
 Identifier tab
 Set