select stringreplace(
由于开发需要,想实现一些提示信息的通用,,比如,提示信息内容:“XXX的值YYY不正确,请检查并重新输入!”,那么,通用的信息内容就应该为:“{0}的值{1}不正确,请检查并重新输入!”。但这个“{0}”和"{1}"怎么替换掉呢?在.net中,字符串有String.Format函数,这样我们就可以很容易地去根据不同的内容,替换成不一样的内容,但Oracle里面还没有样的函数(据个人所知,不知道有没有孤漏寡闻!),但又想用,所以就只能自己写了。
想了想,有问题啊,且听我道来:
信息内容中有多个参数,并且都是用花括号中带数字来表示,如{0},{1},{2},那么,这些参数最好能用数组来表示,但Oracle PL/SQL中有数组吗?都怪自己平时不努力,书到用时方恨少啊。在网上百谷了一下,Oralce里面没有现成的数据类型,只有通过自定义数组类型(其实是Table表结构类型).如下代码所示:
可是问题又来了,用的时候,怎么传值给函数啊?杯具了,纠结了好一会,算了,还是笨一会吧,字符串分割好了。那么这个函数需要什么东东呢?
1.信息内容
2.参数列表(多个参数用分割符分开)
3.分割符(当然是跟2中一致的,不然,可就牛头不对马嘴了)
开始写吧,转头一想,是不是分成两个函数会更好呢?一个用于分割返回参数数组列表,另一个专就是调用分割函数得到参数列表后,做替换的动作,最后返回。en,想想不错,就写成两个吧,功能很单纯,很天真。
俗话说,他山之石,可以攻玉。百谷了一下,分割函数有现成的,拿来吧,请往下看:
1 RETURN returnvalue;
44 END stringsplit;

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MySQLclusteringenhancesdatabaserobustnessandscalabilitybydistributingdataacrossmultiplenodes.ItusestheNDBenginefordatareplicationandfaulttolerance,ensuringhighavailability.Setupinvolvesconfiguringmanagement,data,andSQLnodes,withcarefulmonitoringandpe

Optimizing database schema design in MySQL can improve performance through the following steps: 1. Index optimization: Create indexes on common query columns, balancing the overhead of query and inserting updates. 2. Table structure optimization: Reduce data redundancy through normalization or anti-normalization and improve access efficiency. 3. Data type selection: Use appropriate data types, such as INT instead of VARCHAR, to reduce storage space. 4. Partitioning and sub-table: For large data volumes, use partitioning and sub-table to disperse data to improve query and maintenance efficiency.

TooptimizeMySQLperformance,followthesesteps:1)Implementproperindexingtospeedupqueries,2)UseEXPLAINtoanalyzeandoptimizequeryperformance,3)Adjustserverconfigurationsettingslikeinnodb_buffer_pool_sizeandmax_connections,4)Usepartitioningforlargetablestoi


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