Split .tfrecords file into many .tfrecords files

Is there any way to split .tfrecords file into many .tfrecords files directly, without writing back each Dataset example ?


In tensorflow 2.0.0, this will work:

import tensorflow as tf

raw_dataset = tf.data.TFRecordDataset("input_file.tfrecord")

shards = 10

for i in range(shards):
    writer = tf.data.experimental.TFRecordWriter(f"output_file-part-{i}.tfrecord")
    writer.write(raw_dataset.shard(shards, i))

You can use a function like this:

import tensorflow as tf

def split_tfrecord(tfrecord_path, split_size):
    with tf.Graph().as_default(), tf.Session() as sess:
        ds = tf.data.TFRecordDataset(tfrecord_path).batch(split_size)
        batch = ds.make_one_shot_iterator().get_next()
        part_num = 0
        while True:
            try:
                records = sess.run(batch)
                part_path = tfrecord_path + '.{:03d}'.format(part_num)
                with tf.python_io.TFRecordWriter(part_path) as writer:
                    for record in records:
                        writer.write(record)
                part_num += 1
            except tf.errors.OutOfRangeError: break

For example, to split the file my_records.tfrecord into parts of 100 records each, you would do:

split_tfrecord(my_records.tfrecord, 100)

This would create multiple smaller record files my_records.tfrecord.000, my_records.tfrecord.001, etc.