Queries

•	Enable olap_search_threads: This doradus.yaml file parameter allows multi-shard queries to search shards in parallel using embedded threads. The default value (0) uses single-threaded searching. Increasing this value can significantly improve query performance.

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Search live data with uncommitted=true: By default, object and aggregate queries search only merged batches in the requested shard(s). By adding uncommitted=true to a query, update batches not yet committed are included in the search. As described in the sections titled Multi-shard and Uncommitted Data Queries, there are caveats with this option. But if your update batches only add new objects, this option allows you to query the most recent, “live” data. This option can reduce the frequency with which you merge shards.

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Use paged queries: By default, object queries return 100 objects, and the next page is requested with &g=<continuation token>. Sometimes queries are more efficient with larger page sizes, thereby reducing round trips, or smaller page sizes, which return results more immediately. Grouped aggregate queries are faster when the results are “paged” by using grouping functions such as TOP/BOTTOM or FIRST/LAST.