Errors

They are 4 custom errors describing the reasons why the queries fail and what to do:

  1. InvalidQueryException

  2. ExternalLibraryException

  3. UnauthorizedAccessException

  4. InternalServerException

Additionally, when utilizing a MongoDB administration database, a WriteConcernError (from pymongo.errors) may be triggered if a write operation is not acknowledged. In such instances, the error should be escalated to the server administrator as an InternalServerException.

InvalidQueryException

  • Happens when: error is due to an an invalid query from the user

  • Example: an “opendp” pipeline which is not a measurement, not enough budget for query

  • What to do: Based on the specific error message, the user should check and fix their relevant query parameters.

ExternalLibraryException

  • Happens when: error comes from an external differential privacy library (“smartnoise-sql” or “opendp”).

  • Example: invalid values in Smartnoise-SQL mechanisms parameter.

  • What to do: Based on the specific error message, the user should check and fix their “smartnoise-sql” query parameter or “opendp” pipeline parameter.

UnauthorizedAccessException

  • Happens when: user tries to query a dataset without sufficient authorisation:

    • when the user does not exist,

    • when the user does not have access to the dataset,

    • when the user may not query.

  • Example: user tries to query a dataframe to which they do not have access

  • What to do: The user should decrease the budget parameters and check their access rights.

InternalServerException

  • Happens when: there are internal issues within the server.

  • Example: failed startup of the server

  • What to do: contact the administrative team for help. Users are not responsible for the failure of their request.

This error should never occur while the server is deployed.