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SQL programmingYou can use the HCL OneDB™ implementation of the SQL language to develop applications for HCL OneDB™ database servers.
Guide to SQL: ReferenceThe HCL OneDB™ Guide to SQL: Reference contains the reference information for the system catalog tables, data types, and environment variables of the HCL OneDB™ dialect of the SQL language, as implemented in HCL OneDB™. These topics also include information about the stores_demo, sales_demo, and superstore_demo databases that are included with HCL OneDB™.
Environment variablesVarious environment variables affect the functionality of your HCL OneDB™ products. You can set environment variables that identify your terminal, specify the location of your software and define other parameters.
Environment variables in HCL OneDB™ productsThe topics that follow discuss (in alphabetic order) environment variables that HCL OneDB™ database server products and their utilities use.
RTREE_COST_ADJUST_VALUE environment variable

RTREE_COST_ADJUST_VALUE environment variable

The RTREE_COST_ADJUST_VALUE environment variable specifies a coefficient that support functions of user-defined data types can use to estimate the cost of an R-tree index for queries on UDT columns.

value: is a floating-point number, where 1 ≤ value ≤ 1000, specifying a multiplier for estimating the cost of using an index on a UDT column.

For spatial queries, the I/O overhead tends to exceed by far the CPU cost, so by multiplying the uncorrected estimated cost by an appropriate value from this setting, the database server can make better cost-based decisions on how to implement queries on UDT columns for which an R-tree index exists.

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