Tuning query-related parameters
In this recipe, we will talk about the query planning related parameters and the associated tuning aspects.
How to do it...
The following are the query planning related parameters that usually require tuning:
random_page_costseq_page_costeffective_cache_sizework_memconstraint_exclusion
These parameters can be set in the postgresql.conf configuration file.
How it works...
random_page_cost: This parameter is basically used to estimate the cost of a random page fetch in abstract cost units. The default value of this parameter is 4.0. Random page cost is basically used to represent the coefficient between the cost of looking up one row via sequential scans against the cost of looking up a single row individually using random access, that is, disk seeks. This factor influences the query planner's decision to use indexes instead of a table scan while executing queries. Reducing this value relative to the seq_page_cost parameter will cause the system to prefer...
