Engine configuration options

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 Two emulation options are supported: SQL Azure (default) and SQL Server Enterprise Edition 2012.
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 unchecked 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.