11. DB Sharding 策略
• Sharding is NOT SILVER BULLET for DB Scale-out
• 不适用场景
– 处理事务型应用非常复杂,跨不同DB 事务,很难保证一致性
– 不含Sharding ID 查询较多的场景,即使并行处理,也要全扫描
• 大方向选择(non-global tables)
– Sharding on every table primary separation child separation
– Sharding on every table group (sticky) primary + all children
– Sharding on every table group (non-sticky) primary + some children
• 小策略选择:Sharding ID、Aggregation、etc.