CreateQuery table_to_merge_a (children 3)
 Identifier table_to_merge_a
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration id (children 1)
    DataType UInt64
   ColumnDeclaration val (children 1)
    DataType String
 Storage definition (children 2)
  Function ReplacingMergeTree (children 1)
   ExpressionList
  Identifier id