Apache Arrow 定義了兩種格式，用於序列化資料以進行跨程序通訊 (IPC)：一種是「串流」格式，另一種是「檔案」格式，稱為 Feather。RecordBatchStreamWriter 和 RecordBatchFileWriter 分別是用於將 record batch 寫入這些格式的介面。
若要了解如何使用這些類別，請參閱範例章節。
工廠
RecordBatchFileWriter$create() 和 RecordBatchStreamWriter$create() 工廠方法實例化物件並接受以下參數
sink一個OutputStreamschema要寫入資料的 Schemause_legacy_format邏輯值：寫入格式化的資料，以便 Arrow 程式庫 0.14 及更低版本可以讀取。預設值為FALSE。您也可以透過設定環境變數ARROW_PRE_0_15_IPC_FORMAT=1來啟用此功能。metadata_version：一個字串，例如 “V5” 或指示 Arrow IPC MetadataVersion 的等效整數。預設值 (NULL) 將使用最新版本，除非環境變數ARROW_PRE_1_0_METADATA_VERSION=1，在這種情況下將使用 V4。
方法
$write(x)：寫入 RecordBatch、Table 或data.frame，並適當地分派到以下方法$write_batch(batch)：將RecordBatch寫入串流$write_table(table)：將Table寫入串流$close()：關閉串流。請注意，這表示檔案結尾或串流結尾——它不會關閉與sink的連線。那需要另外關閉。
另請參閱
write_ipc_stream() 和 write_feather() 提供了更簡單的介面，用於將資料寫入這些格式，並且足以應付許多使用案例。write_to_raw() 是一個將資料序列化到緩衝區的版本。
範例
tf <- tempfile()
on.exit(unlink(tf))
batch <- record_batch(chickwts)
# This opens a connection to the file in Arrow
file_obj <- FileOutputStream$create(tf)
# Pass that to a RecordBatchWriter to write data conforming to a schema
writer <- RecordBatchFileWriter$create(file_obj, batch$schema)
writer$write(batch)
# You may write additional batches to the stream, provided that they have
# the same schema.
# Call "close" on the writer to indicate end-of-file/stream
writer$close()
# Then, close the connection--closing the IPC message does not close the file
file_obj$close()
# Now, we have a file we can read from. Same pattern: open file connection,
# then pass it to a RecordBatchReader
read_file_obj <- ReadableFile$create(tf)
reader <- RecordBatchFileReader$create(read_file_obj)
# RecordBatchFileReader knows how many batches it has (StreamReader does not)
reader$num_record_batches
#> [1] 1
# We could consume the Reader by calling $read_next_batch() until all are,
# consumed, or we can call $read_table() to pull them all into a Table
tab <- reader$read_table()
# Call as.data.frame to turn that Table into an R data.frame
df <- as.data.frame(tab)
# This should be the same data we sent
all.equal(df, chickwts, check.attributes = FALSE)
#> [1] TRUE
# Unlike the Writers, we don't have to close RecordBatchReaders,
# but we do still need to close the file connection
read_file_obj$close()