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- 310 registry:skill items, 1528 files, 7 categories (hub tags) - registry.json generated by @kortix/registry buildRegistry - nested SKILL.md in sn-da-* renamed SUBSKILL.md (no phantom skills) - provenance + licenses: SOURCES.md
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| title | impact | impactDescription | tags |
|---|---|---|---|
| Maintain Table Statistics with VACUUM and ANALYZE | MEDIUM | 2-10x better query plans with accurate statistics | vacuum, analyze, statistics, maintenance, autovacuum |
Maintain Table Statistics with VACUUM and ANALYZE
Outdated statistics cause the query planner to make poor decisions. VACUUM reclaims space, ANALYZE updates statistics.
Incorrect (stale statistics):
-- Table has 1M rows but stats say 1000
-- Query planner chooses wrong strategy
explain select * from orders where status = 'pending';
-- Shows: Seq Scan (because stats show small table)
-- Actually: Index Scan would be much faster
Correct (maintain fresh statistics):
-- Manually analyze after large data changes
analyze orders;
-- Analyze specific columns used in WHERE clauses
analyze orders (status, created_at);
-- Check when tables were last analyzed
select
relname,
last_vacuum,
last_autovacuum,
last_analyze,
last_autoanalyze
from pg_stat_user_tables
order by last_analyze nulls first;
Autovacuum tuning for busy tables:
-- Increase frequency for high-churn tables
alter table orders set (
autovacuum_vacuum_scale_factor = 0.05, -- Vacuum at 5% dead tuples (default 20%)
autovacuum_analyze_scale_factor = 0.02 -- Analyze at 2% changes (default 10%)
);
-- Check autovacuum status
select * from pg_stat_progress_vacuum;
Reference: VACUUM