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What are OLTP and OLAP. What is the difference between them?
...more data).
It's a bit more involved than that of course and that's a 20 000 feet overview of how databases differ, but it allows me not to get lost in a sea of acronyms.
Speaking of acronyms:
OLTP = Online transaction processing
OLAP = Online analytical processing
To read a bit further, here...
Should I use multiplication or division?
...t=12341234234.234 * 0.5 end'
real 0m1.843s
user 0m1.676s
sys 0m0.000s
=>it's only 5% faster
conclusions: in Python it's faster to multiply than to divide, but as you get closer to the CPU using more advanced VMs or JITs, the advantage disappears. It's quite possible that a future Py...
Does MySQL included with MAMP not include a config file?
...ally adding the my.cnf file to Application/MAMP/conf/ solved ERROR 2006 (HY000) at line 1357: MySQL server has gone away. This post is old but still relevant for MAMP Version 3.0.2 (not pro)
– C13L0
Mar 16 '14 at 19:25
...
Virtual functions and performance - C++
...it in L1) and ran a loop that added them to one another (A.x = B.x + C.x) 1000 times. I ran this with the functions defined as inline, virtual, and regular function calls. Here are the results:
inline: 8ms (0.65ns per call)
direct: 68ms (5.53ns per call)
virtual: 160ms (13ns per call)
So, i...
SQL query to find record with ID not in another table
...
When i have 20 datas, It works, but when i have 20000 datas, it not work, Iam confuse now.
– Frank
Nov 2 '16 at 3:25
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从Code Review 谈如何做技术 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...的描述——
卡珀斯·琼斯（Capers Jones）分析了超过12,000个软件开发项目，其中使用正式代码审查的项目，发现潜在缺陷率约在60-65%之间，若是非正式的代码审查，发现潜在缺陷率不到50%。大部份的测试，发现的潜在缺陷率会...
CruiseControl [.Net] vs TeamCity for continuous integration?
...sed at larger companies. I've used Perforce and liked it but I was at a 1,000 developer company when I used it.
– Samuel Neff
May 18 '11 at 13:30
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...
jQuery .each() index?
...clicker", function() {
run_each();
});
.results {
background: #000;
height: 150px;
overflow: auto;
color: lime;
font-family: arial;
padding: 20px;
}
.container {
display: flex;
}
.one,
.two,
.three {
width: 33.3%;
}
.one {
background: yellow;
text...
What makes JNI calls slow?
...st can be linear in the size of the array. I measured JNI copying of a 100,000 array to average about 75 microseconds on my Windows desktop, and 82 microseconds on Mac. Fortunately, direct access may be obtained via GetPrimitiveArrayCritical or NewDirectByteBuffer.
If the method is passed an object,...
What is the difference between `new Object()` and object literal notation?
...console.log('Testing Array:');
console.time('using[]');
for(var i=0; i<200000000; i++){var arr = []};
console.timeEnd('using[]');
console.time('using new');
for(var i=0; i<200000000; i++){var arr = new Array};
console.timeEnd('using new');
console.log('Testing Object:');
console.time('using...