> For the complete documentation index, see [llms.txt](https://solr-express.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://solr-express.gitbook.io/docs/5.1.2/tutorials/basic-features/fail-fast.md).

# Fail fast

## Feature

Throw **SearchParameterIsInvalidException** when developer use a field in wrong way

Using a collection with 2 fields with follow settings:

| Field  | Indexed | Stored |
| ------ | ------- | ------ |
| Field1 | False   | True   |
| Field2 | True    | False  |

Use cases:

| Use case     | Using method | Field1           | Field2           |
| ------------ | ------------ | ---------------- | ---------------- |
| Faceting     | FacetField   | Throws exception | Works well       |
| Faceting     | FacetQuery   | Throws exception | Works well       |
| Faceting     | FacetRange   | Throws exception | Works well       |
| Filtering    | Filter       | Throws exception | Works well       |
| Get contents | Fields       | Works well       | Throws exception |
| Search       | Query        | Throws exception | Works well       |
| Sorting      | Sort         | Throws exception | Works well       |

**NOTE**

See more in [**field options by use case**](http://wiki.apache.org/solr/FieldOptionsByUseCase);

## How to

**This feature is actived by default**

To active/inactive this feature, change your **SolrExpressOptions** and set **FailFast**, like below:

```csharp
    services
        .AddSolrExpress<TechProduct>(builder => builder
            .UseOptions(options =>
            {
                // ... Other settings
                options.FailFast = true
            })
            // ...  Other settings
            );
```


---

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