Evidence extracts data from your database to use in reports. Why Extract? To build reports, first you need to import your data. This is all managed in the Sources tab tab in the sidebar. This involves:
  1. Creating a connection to your database
  2. Adding tables as Evidence “sources”
Evidence supports importing data from:

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Create a connection

(For databases only)
  1. On the sources page, click New Connection.
  2. Enter the connection details for your database. Note that you require one connection per schema at this time.
  3. Click Test to verify the connection is configured correctly.
  4. Click Save.

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IP Whitelisting

If your database requires IP whitelisting, add the Evidence Studio IP addresses: 
104.197.50.84
34.56.211.45

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Import a data source

  1. On the sources page, click New Source.
  2. Select the connection you just created.
  3. Choose from the tables in the connection.
  4. (Optional) Rename the source - this is used to reference the source in your reports.
  5. Click Save.

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Import a file

  1. On the sources page, click Upload File.
    • You can upload CSV, Parquet, and JSONL files.
  2. Your file will be automatically imported, and named using a snake_case version of the filename.

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Updating data

You can only update uploaded files by reuploading them.

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Manual refresh

  1. On the sources page, click the ... menu on the right of the source and select Publish.

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Scheduled refresh

  1. In the sources page, click the ... menu on the right of the source and select Schedule.
  2. Choose a refresh interval.
    • Current refresh intervals are: 5 mins, 15 mins, 1 hour, 1 day, 1 week. Contact Evidence for custom intervals.
  3. Click Save.

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Why extract?

Evidence extracts data from your database to use in reports. This has the following benefits:
  • Performance: Extracted data is very fast to query, as it uses a specialized storage format (Parquet), and an optimzed query engine based on ClickHouse.
  • Cross-database: You can join data from different databases, or even join to data in flat files like CSV and Parquet.
  • Control: You can control when data is extracted, and the frequency of the extraction.
  • DB Load: When users access your reports, your database is not queried, only refreshing data causes queries to be run against your database.