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Detect if value is number in MySQL
...l1 * 1) = col1
It doesn't work for non-standard numbers like
1e4
1.2e5
123. (trailing decimal)
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unable to start mongodb local server
...s Jung:
"Sat Jun 25 09:38:51 [initandlisten] listen(): bind() failed errno:98 Address already in use for socket: 0.0.0.0:27017
is self-speaking.
Another instance of mongod is already running and allocating the MongoDB default port which is 27017.
Either kill the other process or use a different port...
How to convert a string to number in TypeScript?
...rrect typing and will correctly parse simple decimal integer strings like "123", but will behave differently for various other, possibly expected, cases (like "123.45") and corner cases (like null).
Table taken from this answer
...
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 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 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...
Calculating distance between two points, using latitude longitude?
...
}
System.out.println(distance(32.9697, -96.80322, 29.46786, -98.53506, 'M') + " Miles\n");
System.out.println(distance(32.9697, -96.80322, 29.46786, -98.53506, 'K') + " Kilometers\n");
System.out.println(distance(32.9697, -96.80322, 29.46786, -98.53506, 'N') + " Nautical Miles\...
Java Byte Array to String to Byte Array
...ue will not be a array anymore. For example :
byte[] b1 = new byte[] {97, 98, 99};
String s1 = Arrays.toString(b1);
String s2 = new String(b1);
System.out.println(s1); // -> "[97, 98, 99]"
System.out.println(s2); // -> "abc";
As you can see, s1 holds the string representatio...
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
...
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...