SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 2)
    Literal \'max_merge_delayed_streams_for_parallel_write=1000\' (alias test)
    Function count (alias count) (children 1)
     ExpressionList
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.part_log
   Function and (children 1)
    ExpressionList (children 5)
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier table
       Literal \'metric_log\'
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier database
       Function currentDatabase (children 1)
        ExpressionList
     Function greaterOrEquals (children 1)
      ExpressionList (children 2)
       Identifier event_date
       Function yesterday (children 1)
        ExpressionList
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier event_type
       Literal \'MergeParts\'
     Function greater (children 1)
      ExpressionList (children 2)
       Identifier peak_memory_usage
       Literal UInt64_1000000000
