Explain EXPLAIN (children 2)
 Set
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 3)
    ExpressionList (children 1)
     Function count (children 1)
      ExpressionList
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier t_skip_index_insert
    Function and (children 1)
     ExpressionList (children 3)
      Function greaterOrEquals (children 1)
       ExpressionList (children 2)
        Identifier a
        Literal UInt64_110
      Function less (children 1)
       ExpressionList (children 2)
        Identifier a
        Literal UInt64_130
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier b
        Literal UInt64_2
