- 不在数据库中做运算,复杂运算移到程序端进行。
- 控制单表数据量,建议单库不超300-400个表,单表不超过50个纯INT字段,单表不超过20个CHAR(10)字段,单行不超过200Byte。
- 操持表字段少而精,IO高效、表修复快、提高并发、alter table快,单表字段控制在20-50个内,并且使用合适的字段类型。
- 平衡范式、适当的字段冗余
- 拒绝大SQL、大事务、大批量,避免使用存储过程
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我来慢慢解释各种问题。 | |
首先是进藏的问题。怎么进,徒步的踏自行车的自驾我就不知道了,不解释了。火车进藏的,票很难刷,介意先去西宁,然后再买西宁到拉萨的票,时间多还可以在西宁呆一天,去青海湖望一眼。我是飞机进藏的,选择飞机的,你在北京天津啊什么的,不要傻了吧唧的直接就买北京到拉萨,天津到拉萨,贵的死死的!和火车一样,迂回战术,先飞成都重庆再到拉萨,尤其是重庆啊,8月机票居然还有287的。而且重庆很方便啊,你飞机来的飞机走就行了,火车来的,坐轻轨3号线直接就到机场了,火车站就可以值机。 | |
然后是高反问题。高反不是病,只是从0海拔到3700海拔的地方不适应而已,没什么怕的,别担心这别担心那的,怕死的可以不去啊。第一天到拉萨的,不管火车飞机,介意好好睡觉好好休息,把饭吃好,别作死到处跑到处逛。我刚到的时候也是没事,吃了饭到处跑,回去的时候开始有点头疼,喝了两粒高原康,19点就睡了,第二天好了,身体素质不好的,第一天就好好休息,别使劲走路活蹦乱跳的。 | |
好多人准备去西藏的时候,就开始准备各种药,我想问准备药干嘛,群里昨天还见一姑娘带了一大堆药,什么消炎感冒药抗高反药不知名药,然后还不停问够了吗?我问她这是要去开药店吗,拉萨什么都有啊!你有个头疼脑热的现买都来得及啊,干嘛要带呢?实在体弱的厉害,红景天提前一个周吃。 | |
火车进藏的怕什么啊,一点一点海拔升上去的啊,飞机进藏的,一下飞机可能没什么事,晚上如果不好好休息没缓过来,就会不舒服,为了不影响后面行程,第一天到的就好好休息吧。 |
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http://d.stavrovski.net/blog/post/how-to-install-and-setup-oracle-java-jdk-in-centos-6 | |
# rpm | |
wget --no-cookies \ | |
--no-check-certificate \ | |
--header "Cookie: oraclelicense=accept-securebackup-cookie" \ | |
"http://download.oracle.com/otn-pub/java/jdk/7u79-b15/jdk-7u79-linux-x64.rpm" \ | |
-O jdk-7-linux-x64.rpm | |
# ubuntu |
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mybatis: http://dunnohe.github.io/2016/07/22/Java-mybatis%E8%BF%94%E5%9B%9E%E4%B8%BB%E9%94%AE%E7%9A%84%E5%9D%91/ | |
SpringMVC4.1之Controller层最佳实践 https://github.com/kuitos/kuitos.github.io/issues/9 | |
Spring中@Async用法总结 http://blog.csdn.net/blueheart20/article/details/44648667 | |
上班族必备 , 日本小哥用深度学习开发识别老板的探测器 ( 附源码 ) http://www.myzaker.com/article/5876bcc01bc8e0be6b000029 |
// Save a copy of this request for debugging.
requestDump, err := httputil.DumpRequest(req, true)
if err != nil {
fmt.Println(err)
}
fmt.Println(string(requestDump))
- 系统自带的Python是2.x,自己需要Python 3.x,测试尝鲜;
- 系统是2.6.x,开发环境是2.7.x
- 由于Mac机器系统保护的原因,默认的Python中无法对PIP一些包升级,需要组建新的Python环境
- 此时需要在系统中安装多个Python,但又不能影响系统自带的Python,即需要实现Python的多版本共存。pyenv就是这样一个Python版本管理器
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04a1881d0212aeebf71e6acc22da6fece934f00a184044d0d04bb4475e2959d11253a317abfe46de7a94ce5df180c73efab60713736642e7e66c3ead69edd59bf4 |
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object "Contract" { | |
code { | |
datacopy(0, dataoffset("runtime"), datasize("runtime")) | |
return(0, datasize("runtime")) | |
} | |
object "runtime" { | |
code { | |
if iszero(calledByOwner()) { revert(0, 0) } | |
switch selector() | |
case 0x00 { |