Configuration parameters

List of Querona’s internal engine configuration options is a follows:

Configuration option	Default value	Requires restart?	Description
SQL Server edition emulation	SQL Azure	Yes	The following emulation options are supported: SQL Azure (default) and SQL Server Enterprise Edition 2012. Emulation of SQL Server Enterprise Edition 2022 is experimental and should not be used for production.
Heartbeat interval seconds	10	No	The interval of a heartbeat in seconds.
Heartbeats missed limit	6	No	In a cluster environment, designates the limit of missed heartbeats.
Max prepared statements in connection	200	No	Max count of prepared statements in a connection.
Execution plan cache invalidation interval (seconds)	10	No	Execution plan cache invalidation interval in seconds.
Cached execution plan unused max age (seconds)	3600	No	Max age of unused cached execution plans.
Execution plan cache size	1000	No	The maximum count of statements kept in the execution plan cache.
Pool size [MB]	256	No	The size of the pool in Megabytes (MB).
Data transfer to federator limit [B]	52428800	No	Maximum data size to be sent to a data source for pushdown.
Min worker threads	100	No	Minimal count of worker threads in a thread pool.
Min completion port threads	100	No	Minimal count of completion port threads in a pool.
Max worker threads	32767	No	Maximum count of worker threads in a thread pool.
Max completion port threads	1000	No	Maximum count of completion port threads in a pool.
Max statements stored	1000	No	Maximum count of stored statements.
Row count of tables without statistics	10000000	No	A default rowcount that query optimizer will use for tables without statistics. Default value of 10.000.000 is optimized for analytical workloads. It is strongly recommended to adjust this value to match your environment.
Primary host connects to all instances on start	false	No	True, in a cluster environment, forces Querona’s Primary Instance to connect to all known instances during boot.
Built-in JVM JAVA_HOME override	empty	Yes	Querona does a good effort to find a supported JVM, but if a specific JVM has to be used, an explicit override of JAVA_HOME environment variable can be provided here.
Built-in JVM classpath (csv)	empty	Yes	A comma-separated list of paths to folders where Querona should look for JDBC drivers and load during boot all that it finds.
TOP push-down over UNION clause	disabled	No	Experimental When enabled, allows Querona to push a TOP clause down directly to a provider if a FROM clause grabs rows from a view/sub-select w/ UNION operator.
Predicate push-down over UNION clause	disabled	No	Experimental When enabled, allows Querona to push-down predicated through the UNION clause(s).