Explain EXPLAIN QUERY TREE (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 x
    Function or (children 1)
     ExpressionList (children 2)
      Function and (children 1)
       ExpressionList (children 2)
        Identifier A
        Function equals (children 1)
         ExpressionList (children 2)
          Function sipHash64 (children 1)
           ExpressionList (children 1)
            Identifier C
          Function sipHash64 (children 1)
           ExpressionList (children 1)
            Identifier D
      Function and (children 1)
       ExpressionList (children 2)
        Identifier B
        Function equals (children 1)
         ExpressionList (children 2)
          Function sipHash64 (children 1)
           ExpressionList (children 1)
            Identifier C
          Function sipHash64 (children 1)
           ExpressionList (children 1)
            Identifier D
