Configuration

EHRbase comes with some options to customize how the AQL engine behaves.

Pagination parameters conflict

Configure how EHRbase reacts when there is a conflict of AQL query LIMIT/OFFSET clauses and fetch/offset query parameters during an AQL query execute request by choosing one of the following strategies:

1. REJECT - EHRbase rejects the query execution if the AQL query contains a LIMIT or OFFSET and the fetch or offset query parameters are also present on the request
2. MIN_FETCH - EHRbase will take the minimum value of LIMIT and fetch and use that one during the query execution; If the query AQL also contains the OFFSET clause, then the request is rejected.

Strategy the execute AQL query requests use when LIMIT/OFFSET are used in combination with fetch/offset query params

Property	ENV	Default value	Supported values
ehrbase.rest.aql.fetch-precedence	EHRBASE_REST_AQL_FETCHPRECEDENCE	REJECT	REJECT, MIN_FETCH

Limit query results by default

To set up data query safeguards EHRbase can be configured with the following limits:

• ehrbase.rest.aql.default-limit - when the AQL query or the request don't specify a LIMIT and fetch the system will use the configured default limit
• ehrbase.rest.aql.max-limit - a hard constraint for the LIMIT clause in any AQL query ran in the system; in case a query exceeds it, an error is reported
• ehrbase.rest.aql.max-limit - a hard constraint for the fetch query parameter in any AQL execute query requests; in case a request exceeds it, an error is reported

Property	ENV	Default value	Supported values
ehrbase.rest.aql.default-limit	EHRBASE_REST_AQL_DEFAULTLIMIT	none	any positive number
ehrbase.rest.aql.max-limit	EHRBASE_REST_AQL_MAXLIMIT	none	any positive number
ehrbase.rest.aql.max-fetch	EHRBASE_REST_AQL_MAXFETCH	none	any positive number

Experimental features

Some supported AQL features are not yet standardized. In order to use such features, a flag must be activated.

• ehrbase.aql.experimental.aql-on-folder.enabled - Support for AQL on FOLDER

Property	ENV	Default value	Supported values
ehrbase.aql.experimental.aql-on-folder.enabled	EHRBASE_AQL_EXPERIMENTAL_AQLONFOLDER_ENABLED	false	true/false