Explain EXPLAIN SYNTAX (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 4)
    ExpressionList (children 1)
     Asterisk
    TablesInSelectQuery (children 3)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier t1
     TablesInSelectQueryElement (children 2)
      TableExpression (children 1)
       TableIdentifier t2
      TableJoin
     TablesInSelectQueryElement (children 2)
      TableExpression (children 1)
       Subquery (alias t3) (children 1)
        SelectWithUnionQuery (children 1)
         ExpressionList (children 1)
          SelectQuery (children 3)
           ExpressionList (children 15)
            Function toNullable (children 1)
             ExpressionList (children 1)
              Literal UInt64_10
            Asterisk
            Function isZeroOrNull (children 1)
             ExpressionList (children 1)
              Literal UInt64_10
            Literal UInt64_10
            Asterisk
            Literal UInt64_10
            Asterisk
            Asterisk
            Literal UInt64_10
            Asterisk
            Asterisk
            Asterisk
            Function assumeNotNull (children 1)
             ExpressionList (children 1)
              Function materialize (children 1)
               ExpressionList (children 1)
                Literal UInt64_10
            Function isNotNull (children 1)
             ExpressionList (children 1)
              Literal UInt64_10
            Identifier a (alias x)
           TablesInSelectQuery (children 1)
            TablesInSelectQueryElement (children 1)
             TableExpression (children 1)
              TableIdentifier t3__fuzz_0
           Function equals (children 1)
            ExpressionList (children 2)
             Function plus (children 1)
              ExpressionList (children 2)
               Function toNullable (children 1)
                ExpressionList (children 1)
                 Function toUInt256 (children 1)
                  ExpressionList (children 1)
                   Literal UInt64_1
               Identifier a
             Identifier b
      TableJoin
    Function equals (children 1)
     ExpressionList (children 2)
      Function if (children 1)
       ExpressionList (children 3)
        Function greater (children 1)
         ExpressionList (children 2)
          Identifier t2.b
          Literal UInt64_0
        Identifier t2.a
        Literal UInt64_0
      Identifier t1.a
    ExpressionList (children 3)
     OrderByElement (children 1)
      Identifier t3.x
     OrderByElement (children 1)
      Identifier t2.a
     OrderByElement (children 1)
      Identifier t1.a
