SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 5)
   ExpressionList (children 1)
    Identifier merge_algorithm
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.part_log
   Function and (children 1)
    ExpressionList (children 3)
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier database
       Function currentDatabase (children 1)
        ExpressionList
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier table
       Literal \'users\'
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier event_type
       Literal \'MergeParts\'
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier event_time_microseconds
   Literal UInt64_1
