How to Distribute Keys Evenly Across Regions?

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This topic has been translated from a Chinese forum by GPT and might contain errors.

Original topic: 如何将 keys 均匀分布在各个region ?

| username: TiDBer_rdb3y58G

The final result shows that the keys are not evenly distributed across the regions.

select count(1) from customer2; -- 25000

select min(_tidb_rowid), max(_tidb_rowid) from customer2; -- 8646911284551352321, 8646911284551377320

split table customer2 between (8646911284551352321) and (8646911284551377320) regions 16;

SELECT
    c.address,
    sum(APPROXIMATE_KEYS),
    count(1)
FROM
    INFORMATION_SCHEMA.TIKV_REGION_STATUS s
    JOIN INFORMATION_SCHEMA.TIKV_REGION_PEERS p ON s.REGION_ID = p.REGION_ID
    JOIN INFORMATION_SCHEMA.TIKV_STORE_STATUS c ON p.store_id = c.store_id 
WHERE
    TABLE_NAME = 'customer2' 
    AND p.is_leader = 1 
    AND APPROXIMATE_KEYS > 0 
    AND is_index = 0
GROUP BY c.address
ORDER BY 1;

+----------------------+-----------------------+----------+
| address              | sum(APPROXIMATE_KEYS) | count(1) |
+----------------------+-----------------------+----------+
| 192.168.145.82:20160 |                  8597 |        6 |
| 192.168.145.83:20160 |                 19778 |        6 |
| 192.168.145.84:20160 |                  8170 |        6 |
+----------------------+-----------------------+----------+
3 rows in set (0.10 sec)