Order Search Execution

Same SQL and data, different access paths

MySQL 8.4.102026-07-12

01 · SOURCE

SQL

1 active fragmentsMySQLLIMIT 20

SELECT o.id, o.ordered_at, o.total_cents, c.id AS customer_id, c.name AS customer_name
FROM customers AS c
JOIN orders AS o ON o.customer_id = c.id
WHERE c.country_code = 'KR'
  AND o.status = 'PAID'
  AND o.ordered_at >= '2025-01-01 00:00:00'
ORDER BY o.ordered_at DESC, o.id DESC
LIMIT 20;

02 · FLOW

Execution Plan

01 / 13

Limit · 20 rows

Result rows: 20

-> Limit: 20 row(s) (cost=27404 rows=20) (actual time=46.4..46.5 rows=20 loops=1)

Nested loop inner join

Result rows: 20

-> Nested loop inner join (cost=27404 rows=13096) (actual time=46.4..46.5 rows=20 loops=1)

Sort · ordered_at DESC, id DESC

Order-filter output: 31348

-> Sort: o.ordered_at DESC, o.id DESC (cost=13216 rows=130962) (actual time=46.1..46.1 rows=378 loops=1)

orders status/date Filter

Order-filter output: 31348

-> Filter: ((o.`status` = 'PAID') and (o.ordered_at >= TIMESTAMP'2025-01-01 00:00:00'))  (cost=13216 rows=130962) (actual time=15.2..37.8 rows=31348 loops=1)

Table scan on orders

Orders scan rows: 131072

-> Table scan on o (cost=13216 rows=130962) (actual time=0.214..28.3 rows=131072 loops=1)

customer country Filter

Result rows: 20

-> Filter: (c.country_code = 'KR') (cost=0.25 rows=0.1) (actual time=894e-6..898e-6 rows=0.0529 loops=378)

customers PRIMARY lookup

Customer lookup loops: 378

-> Single-row index lookup on c using PRIMARY (id=o.customer_id)  (cost=0.25 rows=1) (actual time=720e-6..747e-6 rows=1 loops=378)

STEP · RESULT

Open the execution-plan root

Limit returns at most 20 rows. In this capture, the first row arrived at 46.4 ms and all 20 rows completed at 46.5 ms.

First-row time46.4 ms

Last-row time46.5 ms

Result rows20

OPERATOR METRICSCaptured

Limit · 20 rowsline:1

ACCESS: -
SELECTED KEY: -
EST. ROWS: 20
FILTERED: -
COST: 27404
ACTUAL ROWS: 20
LOOPS: 1
ACTUAL TIME: 46.4..46.5 ms

-> Limit: 20 row(s) (cost=27404 rows=20) (actual time=46.4..46.5 rows=20 loops=1)

EXPLAIN ANALYZECaptured

-> Limit: 20 row(s)  (cost=27404 rows=20) (actual time=46.4..46.5 rows=20 loops=1)
    -> Nested loop inner join  (cost=27404 rows=13096) (actual time=46.4..46.5 rows=20 loops=1)
        -> Sort: o.ordered_at DESC, o.id DESC  (cost=13216 rows=130962) (actual time=46.1..46.1 rows=378 loops=1)
            -> Filter: ((o.`status` = 'PAID') and (o.ordered_at >= TIMESTAMP'2025-01-01 00:00:00'))  (cost=13216 rows=130962) (actual time=15.2..37.8 rows=31348 loops=1)
                -> Table scan on o  (cost=13216 rows=130962) (actual time=0.214..28.3 rows=131072 loops=1)
        -> Filter: (c.country_code = 'KR')  (cost=0.25 rows=0.1) (actual time=894e-6..898e-6 rows=0.0529 loops=378)
            -> Single-row index lookup on c using PRIMARY (id=o.customer_id)  (cost=0.25 rows=1) (actual time=720e-6..747e-6 rows=1 loops=378)

Captured · Operators, metrics, results, and resident-page inventory from the MySQL 8.4.10 capture.

.workbench-shell { display: none !important; } .noscript-explanation { display: block !important; }

Full explanation

Performance Schema recorded rowsExamined=131,828, sortRows=31,348, and noIndexUsed=1.

SELECT
    o.id,
    o.ordered_at,
    o.total_cents,
    c.id AS customer_id,
    c.name AS customer_name
FROM customers AS c
JOIN orders AS o
    ON o.customer_id = c.id
WHERE c.country_code = 'KR'
  AND o.status = 'PAID'
  AND o.ordered_at >= '2025-01-01 00:00:00'
ORDER BY o.ordered_at DESC, o.id DESC
LIMIT 20;

EXPLAIN ANALYZE
-> Limit: 20 row(s)  (cost=27404 rows=20) (actual time=46.4..46.5 rows=20 loops=1)
    -> Nested loop inner join  (cost=27404 rows=13096) (actual time=46.4..46.5 rows=20 loops=1)
        -> Sort: o.ordered_at DESC, o.id DESC  (cost=13216 rows=130962) (actual time=46.1..46.1 rows=378 loops=1)
            -> Filter: ((o.`status` = 'PAID') and (o.ordered_at >= TIMESTAMP'2025-01-01 00:00:00'))  (cost=13216 rows=130962) (actual time=15.2..37.8 rows=31348 loops=1)
                -> Table scan on o  (cost=13216 rows=130962) (actual time=0.214..28.3 rows=131072 loops=1)
        -> Filter: (c.country_code = 'KR')  (cost=0.25 rows=0.1) (actual time=894e-6..898e-6 rows=0.0529 loops=378)
            -> Single-row index lookup on c using PRIMARY (id=o.customer_id)  (cost=0.25 rows=1) (actual time=720e-6..747e-6 rows=1 loops=378)