中等水平的设计可能就像



*有一个表COUNTERS（ID，currentValue，maskingRules）

*有值（1,1，'yymmdd9999'）

*有一个SQL函数关注

*阅读掩蔽规则

*解析它并相应填写

*更新CurrentValue

*返回业务层的累计价值



这将有助于以下方式

*您有一个可以轻松测试的独立功能

*您可以定义不同的屏蔽规则

*您可以立即更改规则（在制作时）



这种方法确实有副作用，重要的一个是COUNTERS表，如果定义了太多的计数器，就会因为锁而自行成为负载的瓶颈

A moderate level design could be like

* Have a table COUNTERS(ID, currentValue, maskingRules)
* With values (1, 1, 'yymmdd9999')
* Have a SQL Function which does following
* Read masking rule
* Parse it and fill it accordingly
* Update CurrentValue
* Return the accumulated value to the business layer

This will help in following ways
* You have an independent function that can be easily tested
* You can define different masking rules
* You can change the rules instantly (on production)

This approach do have side effects, significant one is the COUNTERS table could it self be a bottleneck on load because of locks if too many counters have been defined