Explain EXPLAIN QUERY TREE (children 1)
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 3)
    ExpressionList (children 1)
     Asterisk
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier 02952_disjunction_optimization
    Function or (children 1)
     ExpressionList (children 2)
      Function and (children 1)
       ExpressionList (children 3)
        Function notEquals (children 1)
         ExpressionList (children 2)
          Identifier a
          Literal UInt64_1
        Function notEquals (children 1)
         ExpressionList (children 2)
          Identifier a
          Literal UInt64_2
        Function notEquals (children 1)
         ExpressionList (children 2)
          Identifier a
          Literal UInt64_4
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier b
        Literal \'\'
