--- title: Data Management Example --- In this example we'll create a simple dataset and demonstrate basic actions on it. ## Prerequisites First, make sure that you have cloned the [clearml](https://github.com/allegroai/clearml) repository. This contains all the needed files. 1. Open terminal and change directory to the cloned repository's examples folder `cd clearml/examples/reporting` ## Creating initial dataset 1. To create the dataset, run this code: ```bash clearml-data create --project datasets --name HelloDataset ``` Expected response: ```bash clearml-data - Dataset Management & Versioning CLI Creating a new dataset: New dataset created id=24d05040f3e14fbfbed8edb1bf08a88c ``` 1. Now let's add a folder. File addition is recursive, so it's enough to point at the folder to captures all files and subfolders: ```bash clearml-data add --files data_samples ``` Expected response: ```bash clearml-data - Dataset Management & Versioning CLI Adding files/folder to dataset id 24d05040f3e14fbfbed8edb1bf08a88c Generating SHA2 hash for 2 files Hash generation completed 5 files added ``` :::note After creating a dataset, we don't have to specify its ID when running commands, such as *add*, *remove* or *list* ::: 1. Close the dataset - this command uploads the files. By default, the files are uploaded to the file server, but this can be configured with the `--storage` flag to any of ClearML's supported storage mediums (see [storage](../../integrations/storage.md)). The command also finalizes the dataset, making it immutable and ready to be consumed. ```bash clearml-data close ``` Expected response: ```bash clearml-data - Dataset Management & Versioning CLI Finalizing dataset id 24d05040f3e14fbfbed8edb1bf08a88c Pending uploads, starting dataset upload to https://files.community-master.hosted.allegro.ai Pending uploads, starting dataset upload to https://files.community.clear.ml Uploading compressed dataset changes (4 files, total 221.56 KB) to https://files.community.clear.ml Upload completed (221.56 KB) 2021-05-04 09:32:03,388 - clearml.Task - INFO - Waiting to finish uploads 2021-05-04 09:32:04,067 - clearml.Task - INFO - Finished uploading Dataset closed and finalized ``` ## Listing Dataset content To see that all the files were added to the created dataset, use `clearml-data list` and enter the ID of the dataset that was just closed. ```bash clearml-data list --id 24d05040f3e14fbfbed8edb1bf08a88c ``` Expected response: ```console clearml-data - Dataset Management & Versioning CLI List dataset content: 24d05040f3e14fbfbed8edb1bf08a88c Listing dataset content file name | size | hash ------------------------------------------------------------------------------------------------------------------------------------------------ dancing.jpg | 40,484 | 78e804c0c1d54da8d67e9d072c1eec514b91f4d1f296cdf9bf16d6e54d63116a data.csv | 21,440 | b618696f57b822cd2e9b92564a52b3cc93a2206f41df3f022956bb6cfe4e7ad5 picasso.jpg | 114,573 | 6b3c67ea9ec82b09bd7520dd09dad2f1176347d740fd2042c88720e780691a7c sample.json | 132 | 9c42a9a978ac7a71873ebd5c65985e613cfaaff1c98f655af0d2ee0246502fd7 sample.mp3 | 72,142 | fbb756ae14005420ff00ccdaff99416bebfcea3adb7e30963a69e68e9fbe361b Total 5 files, 248771 bytes ``` ## Creating a Child Dataset In Clear Data, it's possible to create datasets that inherit the content of other datasets, there are called child datasets. 1. Create a new dataset, specifying the previously created one as its parent: ```bash clearml-data create --project datasets --name HelloDataset-improved --parents 24d05040f3e14fbfbed8edb1bf08a88c ``` :::note You'll need to input the Dataset ID you received when created the dataset above ::: 1. Now, we want to add a new file. * Create a new file: `echo "data data data" > new_data.txt` (this will create the file `new_data.txt`), * Now add the file to the dataset: ```bash clearml-data add --files new_data.txt ``` Which should return this output: ```console clearml-data - Dataset Management & Versioning CLI Adding files/folder to dataset id 8b68686a4af040d081027ba3cf6bbca6 1 file added ``` 1. Let's also remove a file. We'll need to specify the file's full path (within the dataset, not locally) to remove it. ```bash clearml-data remove --files data_samples/dancing.jpg ``` Expected response: ```bash clearml-data - Dataset Management & Versioning CLI Removing files/folder from dataset id 8b68686a4af040d081027ba3cf6bbca6 1 files removed ``` 1. Close and finalize the dataset ```bash clearml-data close ``` 1. Let's take a look again at the files in the dataset: ``` clearml-data list --id 8b68686a4af040d081027ba3cf6bbca6 ``` And we see that our changes have been made! `new_data.txt` has been added, and `dancing.jpg` has been removed. ``` file name | size | hash ------------------------------------------------------------------------------------------------------------------------------------------------ data.csv | 21,440 | b618696f57b822cd2e9b92564a52b3cc93a2206f41df3f022956bb6cfe4e7ad5 new_data.txt | 15 | 6df986a2154902260a836febc5a32543f5337eac60560c57db99257a7e012051 picasso.jpg | 114,573 | 6b3c67ea9ec82b09bd7520dd09dad2f1176347d740fd2042c88720e780691a7c sample.json | 132 | 9c42a9a978ac7a71873ebd5c65985e613cfaaff1c98f655af0d2ee0246502fd7 sample.mp3 | 72,142 | fbb756ae14005420ff00ccdaff99416bebfcea3adb7e30963a69e68e9fbe361b Total 5 files, 208302 bytes ``` By using `clearml-data`, a clear lineage is created for the data. As seen in this example, when a dataset is closed, the only way to add or remove data is to create a new dataset, and using the previous dataset as a parent. This way, the data is not reliant on the code and is reproducible.