---
# System prepended metadata

title: Query "chain-of-repos provenances"

---

# Query "chain-of-repos provenances" 

## Example use case within omnibenchmark


[This method project](https://renkulab.io/projects/omnibenchmark/omni_batch/mnn-omni-batch) runs a method called *mnn* as part of omnibenchmark. As input it uses preprocessed (e.g., normalized counts) files, that are imported as renku dataset **omni_batch_processed** and generated in [this preprocessing project](https://renkulab.io/projects/omnibenchmark/omni_data/omni-batch-processed). Preprocessing is done in a standardized way on all renku datasets with the keyword *omni_batch* (e.g, **cellbench** and **csf_patient** datasets, which are generated [here](https://renkulab.io/projects/omnibenchmark/omni_data/cellbench) and [here](https://renkulab.io/projects/omnibenchmark/omni_data/csf-patients)).  Besides the processed counts files **omni_batch_processed** dataset contains meta data files for each of the original datasets:

``` bash
renku dataset ls-files omni_batch_processed
omni_batch_processed  2021-06-04 12:59:51   175 KB  data/omni_batch_processed/meta_csf_patient.json       
omni_batch_processed  2021-06-04 12:59:51   102 KB  data/omni_batch_processed/meta_cellbench.json            
omni_batch_processed  2021-06-04 12:59:51    44 MB  data/omni_batch_processed/norm_counts_cellbench.mtx.gz  
omni_batch_processed  2021-06-04 12:59:51   9.2 MB  data/omni_batch_processed/norm_counts_csf_patient.mtx.gz  
```

In the method project we want to run the method *mnn* on all `norm_counts_*.mtx.gz` and their corresponding `meta_*.json` by generating one renku workflow per original dataset (so one workflow per `norm_counts_*.mtx.gz`).
In the moment we find the corresponding meta file by matching names between `meta_*.json` and `norm_counts_*.mtx.gz`. As we can not be sure that our user comply with our naming scheme, a cross-repository query to identify the corresponding original dataset and so `meta_*.json` for each`norm_counts_*.mtx.gz` would be more robust. This is even more relevant for final output files of omnibenchmark, when we would like to track back which dataset and method a result file originates from.

### Example query

From within [mnn_omni_batch](https://renkulab.io/projects/omnibenchmark/omni_batch/mnn-omni-batch) find the **dataset id** of the dataset, that was used as input to generate `data/omni_batch_processed/norm_counts_cellbench.mtx.gz`. Query should give the **dataset_id** of the *cellbench* dataset.

### Scheme

![](https://i.imgur.com/J2c4wv4.png)



