Query Tuning Parameters
Pivotal Query Optimizer Configuration Parameters
- optimizer
- optimizer_analyze_root_partition
- optimizer_control
Query Plan Operator Control Parameters
The following parameters control the types of plan operations the legacy query optimizer can use. Enable or disable plan operations to force the legacy query optimizer to choose a different plan. This is useful for testing and comparing query performance using different plan types.
enable_bitmapscan enable_groupagg enable_hashagg enable_hashjoin enable_indexscan enable_mergejoin enable_nestloop enable_seqscan enable_sort enable_tidscan gp_enable_adaptive_nestloop gp_enable_agg_distinct |
gp_enable_agg_distinct_pruning gp_enable_direct_dispatch gp_enable_fallback_plan gp_enable_fast_sri gp_enable_groupext_distinct_ gather gp_enable_groupext_distinct_ pruning gp_enable_multiphase_agg gp_enable_predicate_ propagation gp_enable_preunique gp_enable_sequential_window_ plans gp_enable_sort_distinct gp_enable_sort_limit |
Legacy Query Optimizer Costing Parameters
cpu_index_tuple_cost cpu_operator_cost cpu_tuple_cost cursor_tuple_fraction effective_cache_size |
gp_motion_cost_per_row gp_segments_for_planner random_page_cost seq_page_cost |
Database Statistics Sampling Parameters
These parameters adjust the amount of data sampled by an ANALYZE operation. Adjusting these parameters affects statistics collection system-wide. You can configure statistics collection on particular tables and columns by using the ALTER TABLE SET STATISTICS clause.
- default_statistics_target
- gp_analyze_relative_error
Sort Operator Configuration Parameters
- gp_enable_sort_distinct
- gp_enable_sort_limit
Aggregate Operator Configuration Parameters
gp_enable_agg_distinct gp_enable_agg_distinct_pruning gp_enable_multiphase_agg gp_enable_preunique |
gp_enable_groupext_distinct_ gather gp_enable_groupext_distinct_ pruning gp_workfile_compress_algorithm |
Join Operator Configuration Parameters
join_collapse_limit gp_adjust_selectivity_for_outerjoins gp_hashjoin_tuples_per_bucket |
gp_statistics_use_fkeys gp_workfile_compress_algorithm |
Other Legacy Query Optimizer Configuration Parameters
- from_collapse_limit
- gp_enable_predicate_propagation
- gp_max_plan_size
- gp_statistics_pullup_from_child_partition