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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...
How do I split a string, breaking at a particular character?
...h JavaScript’s String.prototype.split function:
var input = 'john smith~123 Street~Apt 4~New York~NY~12345';
var fields = input.split('~');
var name = fields[0];
var street = fields[1];
// etc.
share
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...
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...
Redis消息通知系统的实现 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...ontent content3
再把这三条消息发送给某个用户，其<USRID>是123：
redis> SADD usr:123:msg 1
redis> SADD usr:123:msg 2
redis> SADD usr:123:msg 3
此时如果简单查询用户有哪些消息的话，无疑只能查到一些<MSGID>：
redis> SMEMBERS usr:123:msg
1) "1"
2) "2...
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...
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 // ...
Custom circle button
...t;
<corners android:radius="1000dp" />
<solid android:color="#41ba7a" />
<stroke
android:width="2dip"
android:color="#03ae3c" />
<padding
android:bottom="4dp"
android:left="4dp"
android:right="4dp"
android:top="4dp" />
</shape>
...
C# DateTime to “YYYYMMDDHHMMSS” format
...e has great examples check it out
// create date time 2008-03-09 16:05:07.123
DateTime dt = new DateTime(2008, 3, 9, 16, 5, 7, 123);
String.Format("{0:y yy yyy yyyy}", dt); // "8 08 008 2008" year
String.Format("{0:M MM MMM MMMM}", dt); // "3 03 Mar March" month
String.Format("{0:d ...
How can I parse a string with a comma thousand separator to a number?
...1), '.');
return parseFloat(normalized);
}
const corpus = {
'1.123': {
expected: 1.123,
locale: 'en-US'
},
'1,123': {
expected: 1123,
locale: 'en-US'
},
'2.123': {
expected: 2123,
locale: 'fr-FR'
},
'2,123': {
expected: 2.123,
loc...