axolotl/docs/dataset-formats/pretraining.qmd

---
title: Pre-training
description: Data format for a pre-training completion task.
order: 1
---

For pretraining, there is no prompt template or roles.  The only required field is `text`:

```{.json filename="data.jsonl"}
{"text": "first row"}
{"text": "second row"}
...
```

:::{.callout-note}

### Streaming is recommended for large datasets

Axolotl usually loads the entire dataset into memory. This will be challenging for large datasets. Use the following config to enable streaming:

```{.yaml filename="config.yaml"}
pretraining_dataset:
  - name:
    path:
    split:
    text_column: # column in dataset with the data, usually `text`
    type: pretrain
    trust_remote_code:
    skip: # number of rows of data to skip over from the beginning
```

:::