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MySQL Conditional Insert
...nsert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = 123
AND item = 456)
In this, dual is a table with one row only (found orig...
CSS: bolding some text without changing its container's size
...important; text-shadow: none!important; }
<li class="shadow0">MmmIii123 This line tests shadow0 (plain)</li>
<li class="shadow2">MmmIii123 This line tests shadow2 (0.02ex)</li>
<li class="shadow4">MmmIii123 This line tests shadow4 (0.04ex)</li>
<li class="s...
How to find elements with 'value=x'?
I need to remove element that have value="123" . I know that all elements with different values are located into #attached_docs , but I don't know how to select element with value="123" .
...
Difference between == and ===
... me at least))
With strings we will have to get used to this:
var st = "123" // "123"
var ns = (st as NSString) // "123"
st == ns // true, content equality
st === ns // ...
How to print pandas DataFrame without index
... len(df)
df.index=blankIndex
If we use the data from your post:
row1 = (123, '2014-07-08 00:09:00', 1411)
row2 = (123, '2014-07-08 00:49:00', 1041)
row3 = (123, '2014-07-08 00:09:00', 1411)
data = [row1, row2, row3]
#set up dataframe
df = pd.DataFrame(data, columns=('User ID', 'Enter Time', 'Acti...
Fastest way to convert string to integer in PHP
Using PHP, what's the fastest way to convert a string like this: "123" to an integer?
8 Answers
...
What exactly is Type Coercion in Javascript?
...tically (on-the-fly) converts a variable from one datatype to another
Ex: 123 + "4" generally raises an error but in Javascript due to type coercion, it results in 1234 a string
if(23 == "23"){
console.log(" this line is inside the loop and is executed ");
}
In the above code, because of typ...
Simple Pivot Table to Count Unique Values
...s two different columns. Using the original example, I didn't have:
ABC 123
ABC 123
ABC 123
DEF 456
DEF 567
DEF 456
DEF 456
and want it to appear as:
ABC 1
DEF 2
But something more like:
ABC 123
ABC 123
ABC 123
ABC 456
DEF 123
DEF 456
D...
Difference between matches() and find() in Java Regex
...
Pattern p = Pattern.compile("\\d\\d\\d");
Matcher m = p.matcher("a123b");
System.out.println(m.find());
System.out.println(m.matches());
p = Pattern.compile("^\\d\\d\\d$");
m = p.matcher("123");
System.out.println(m.find());
System.out.println(m.matches());
}
/* ou...
LR性能指标解释 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...。
4.JMap。监控java程序是否有内存泄漏，需要配合eclipse插件或者MemoryAnalyzer来使用。
5.JProfiler。全面监控每个节点的CPU使用率、内存使用率、响应时间累计值、线程执行情况等，需要在JVM参数中进行配置。
6.Nmon。全面监控linux...