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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
System administrationThese topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL OneDB™ database servers.
Performance GuideThe HCL OneDB™ Performance Guide describes how to configure and operate your HCL OneDB™ database server to improve overall system throughput and to improve the performance of SQL queries.
Indexes and index performance considerationsHCL OneDB™ provides several types of indexes. Some performance issues are associated with indexes.
Improve query performance with a forest of trees indexA forest of trees index is an alternate indexing method that alleviates the performance bottlenecks and root node contention that can occur when many concurrent users access a traditional B-tree index.
Determining if you are using a forest of trees indexYou can determine whether an index is a forest of trees index by viewing SET EXPLAIN output. A forest of trees index has FOT in the Index Name field of the output.

Determining if you are using a forest of trees index

You can determine whether an index is a forest of trees index by viewing SET EXPLAIN output. A forest of trees index has FOT in the Index Name field of the output.

Example

In the following example of partial SET EXPLAIN output, informix.fot_idx is the name of a forest of trees index.

Estimated Cost: 1
Estimated # of Rows Returned: 1

  1) informix.t: INDEX PATH

    (1) Index Name: informix.fot_idx (FOT)
        Index Keys: c1 c2   (Serial, fragments: ALL)
        Lower Index Filter: informix.t.c1 = 1