> ## Documentation Index
> Fetch the complete documentation index at: https://docs.openlayer.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Duplicate rows

> Learn how to use the duplicate rows test

## Definition

The duplicate rows test checks if there are rows that are identical to each other in the dataset.

## Taxonomy

* **Task types**: LLM, tabular classification, tabular regression, text classification.
* **Availability**: development (Continuously evaluate your models and datasets as you iterate on their versions.)
  and monitoring (Monitor a model in production, measure its health, check for drifts and set up alerts.).

## Why it matters

* Duplicate rows on the training set can lead the model to overfit on the duplicated examples.
* Duplicate rows on the validation set can distort the [aggregate metrics](https://docs.openlayer.com/tests/performance/aggregate-metrics#available-metrics), making them overly optimistic or pessimistic.

## Test configuration examples

If you are writing a `tests.json`, here are a few valid configurations for the character length test:

```json Development theme={null}
[
  {
    "name": "No duplicate rows",
    "description": "Asserts that there are no duplicate rows",
    "type": "integrity",
    "subtype": "duplicateRowCount",
    "thresholds": [
      {
        "insightName": "duplicateRowCount",
        "measurement": "duplicateRowCount",
        "operator": "<=",
        "value": 0
      }
    ],
    "subpopulationFilters": null,
    "mode": "development",
    "usesValidationDataset": true,
    "usesTrainingDataset": false,
    "usesMlModel": false,
    "syncId": "b4dee7dc-4f15-48ca-a282-63e2c04e0689"
  },
  {
    "name": "No duplicate rows",
    "description": "Asserts that there are no duplicate rows",
    "type": "integrity",
    "subtype": "duplicateRowCount",
    "thresholds": [
      {
        "insightName": "duplicateRowCount",
        "measurement": "duplicateRowPercentage",
        "operator": "<=",
        "value": 0.0
      }
    ],
    "subpopulationFilters": null,
    "mode": "development",
    "usesValidationDataset": true,
    "usesTrainingDataset": false,
    "usesMlModel": false,
    "syncId": "96622fba-ea00-4e42-8f42-5e8f5f60805f"
  }
]
```

```json Monitoring theme={null}
[
  {
    "name": "No duplicate rows",
    "description": "Asserts that there are no duplicate rows",
    "type": "integrity",
    "subtype": "duplicateRowCount",
    "thresholds": [
      {
        "insightName": "duplicateRowCount",
        "measurement": "duplicateRowCount",
        "operator": "<=",
        "value": 0
      }
    ],
    "subpopulationFilters": null,
    "mode": "monitoring",
    "usesProductionData": true,
    "evaluationWindow": 3600,
    "delayWindow": 0,
    "syncId": "b4dee7dc-4f15-48ca-a282-63e2c04e0689"
  },
  {
    "name": "No duplicate rows",
    "description": "Asserts that there are no duplicate rows",
    "type": "integrity",
    "subtype": "duplicateRowCount",
    "thresholds": [
      {
        "insightName": "duplicateRowCount",
        "measurement": "duplicateRowPercentage",
        "operator": "<=",
        "value": 0.0
      }
    ],
    "subpopulationFilters": null,
    "mode": "monitoring",
    "usesProductionData": true,
    "evaluationWindow": 3600,
    "delayWindow": 0,
    "syncId": "96622fba-ea00-4e42-8f42-5e8f5f60805f"
  }
]
```


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