CreateQuery 03250_avoid_prefetch (children 3)
 Identifier 03250_avoid_prefetch
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration id (children 1)
    DataType UInt64
   ColumnDeclaration string (children 1)
    DataType LowCardinality (children 1)
     ExpressionList (children 1)
      DataType String
 Storage definition (children 3)
  Function MergeTree
  Identifier id
  Set
