Enabling Sample Mode in MongoDB Charts restricts the input
1000 randomly selected documents. To toggle
Sample Mode, use the toggle above the
Data Source dropdown. The sample mode setting for a chart
persists when the chart is rendered on a dashboard, meaning that if
you enable sample mode when building a chart, the data rendered in the
dashboard will also be sampled.
When sampling mode is enabled and you have specified a
filter, the sample of
documents is taken before the filter is applied, meaning there may
be fewer than
1000 documents used to plot the chart.
Consider using sample mode in the following scenarios:
- When drafting a chart and heavily modifying chart options. In this situation, sampling mode allows the chart to render quickly during the building process. Once you are satisfied with your chart you can disable sample mode to have all documents included in your final visualization if desired.
- When visualizing a large data source and the chosen data is sufficiently aggregated (e.g. showing averages of fields) so not all documents are needed to obtain a useful visualization. In this case, leaving sample mode enabled for the rendered dashboard allows you to retain a useful chart.
Due to the random nature of sampling, when Sample Mode is enabled, it is possible your visualizations will change each time the chart is loaded.