Tag

#indexes 1 post

> EXPLAIN SELECT * FROM volumes WHERE uuid = 'x';

                  info
------------------------------------------
  • scan
    table: volumes@volumes_pkey
    spans: FULL SCAN                        ← here

  index recommendations: 1
    1. CREATE INDEX ON volumes (uuid) STORING (...);

Database · Troubleshooting

CockroachDB indexeswhy it still read 200,000 rows after I added one

A cluster resource list query was slow in internal testing, so I added indexes. Execution time dropped from 233ms to 104ms and I thought it was fixed. Then EXPLAIN ANALYZE showed rows read going from 205,000 to 200,025, barely changed. The numbers didn't add up.

Aug 28, 2026