Initial work on materialized views

[thokra-nav]

Using materialized views will create a copy of the data in a preprocessed and stored way for postgresql to do more efficient queries against.

Some quick numbers from my local setup, non-scientific, using NAV data:

Query	Before	After	QI Avg
MonthlyCostForTeam	236.52ms	514μs	2.288s
DailyEnvCostForTeam	16.9ms	14.96ms	-
ResourceUtilizationRangeForTeam	254.88ms	462μs	1.439s

QI Avg: Average execution time as reported by Query Insights for live NAV environment

Pros

• Potential way quicker queries (moving time to updating the view)

Cons

• Extra storage
• Must remember to refresh views when source changes
• A bit more clunky to change queries if the source needs a change

Some more testing needs to be done to verify the usefulness of each materialized view.
Need to create trigger when the source changes.

[thokra-nav]

Laget litt benchmark for de forskjellige spørringene, er litt mer jobb å gjøre:

                                             │   before.txt    │               after.txt                │
                                             │     sec/op      │    sec/op      vs base                 │
ResourceUtilizationRangeForTeam_exists-8        80314.0µ ± 33%    100.3µ ±  7%   -99.88% (p=0.000 n=10)
ResourceUtilizationRangeForTeam_not_exists-8      283.6µ ±  1%    104.9µ ±  4%   -63.00% (p=0.000 n=10)
MonthlyCostForApp-8                              2005.1µ ± 14%    159.4µ ±  5%   -92.05% (p=0.000 n=10)
MonthlyCostForTeam-8                           136728.1µ ±  1%    172.2µ ±  4%   -99.87% (p=0.000 n=10)
DailyEnvCostForTeam-8                             268.0µ ±  8%    139.6µ ±  5%   -47.90% (p=0.000 n=10)
DailyEnvCostForTeam_with_env-8                    7.402m ±  6%    7.755m ±  2%    +4.76% (p=0.007 n=10)
ResourceUtilizationRangeForTeam-8              103422.0µ ±  9%    155.9µ ± 26%   -99.85% (p=0.000 n=10)
ResourceUtilizationRangeForApp-8                15345.6µ ±  4%    167.2µ ±  5%   -98.91% (p=0.000 n=10)
ResourceUtilizationForTeam-8                   200905.8µ ±  3%    900.7µ ±  1%   -99.55% (p=0.000 n=10)
SpecificResourceUtilizationForTeam-8              933.1µ ±  9%   2413.5µ ±  3%  +158.65% (p=0.000 n=10)
AverageResourceUtilizationForTeam-8              47.553m ±  7%    2.740m ±  2%   -94.24% (p=0.000 n=10)

[thokra-nav]

Fra datasettet jeg har, som tilsvarer NAV 6. mars 2024, så er følgende disk i bruk:

Tabell/View	Størrelse
cost	627 MB
cost_monthly_team*	424 kB
cost_monthly_app*	12 MB
cost_daily_team*	317 MB
resource_utilization_metrics	6650 MB
resource_team_range*	40 kB
resource_app_range*	800 kB
resource_utilization_team*	361 MB

• Materialized views

Så for cost er det en økning på ~50%, mens det er ~5% for resource_utilization_metrics

Data hentet via

SELECT pg_size_pretty(pg_total_relation_size('"public"."<table/view>"'));`