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Use '=' or LIKE to compare strings in SQL?
...
To see the performance difference, try this:
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name = B.name
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name LIKE B.name
Comparing strings with '=' is muc...
Javascript and regex: split string and keep the separator
...ositive) lookahead so that the regular expression asserts that the special character exists, but does not actually match it:
string.split(/<br \/>(?=&#?[a-zA-Z0-9]+;)/g);
See it in action:
var string = "aaaaaa<br />&dagger; bbbb<br />&Dagger; cccc";
console.log...
Convert int to char in java
...
int a = 1;
char b = (char) a;
System.out.println(b);
will print out the char with ascii value 1 (start-of-heading char, which isn't printable).
int a = '1';
char b = (char) a;
System.out.println(b);
will print out the char with asc...
Why is String.chars() a stream of ints in Java 8?
In Java 8, there is a new method String.chars() which returns a stream of int s ( IntStream ) that represent the character codes. I guess many people would expect a stream of char s here instead. What was the motivation to design the API this way?
...
Maximum length of the textual representation of an IPv6 address?
...
45 characters.
You might expect an address to be
0000:0000:0000:0000:0000:0000:0000:0000
8 * 4 + 7 = 39
8 groups of 4 digits with 7 : between them.
But if you have an IPv4-mapped IPv6 address, the last two groups can b...
Which are more performant, CTE or temporary tables?
...(A INT IDENTITY PRIMARY KEY, B INT , F CHAR(8000) NULL);
INSERT INTO T(B)
SELECT TOP (1000000) 0 + CAST(NEWID() AS BINARY(4))
FROM master..spt_values v1,
master..spt_values v2;
Example 1
WITH CTE1 AS
(
SELECT A,
ABS(B) AS Abs_B,
F
FROM T
)
SELECT *
FROM CTE1
WHERE A = 780
...
Is there a way to check if a file is in use?
...is closed after I'm done. I think you'll find that the using() {} is less characters than try {} finally { obj.Dispose() }. You'll also find that you now need to declare your object reference outside the using statement, which is more typing. If you have a explicit interface you'd also have to cas...
How do you implement a class in C? [closed]
...n(Object *self);
/// Person.h
typedef struct Person {
Object obj;
char *name;
} Person;
int Person_init(Person *self, char *name);
int Person_greet(Person *self);
int Person_clean(Person *self);
/// Object.c
#include "object.h"
int Object_init(Object *self)
{
self->uuid = uuid_new...
Alternative to itoa() for converting integer to string C++? [duplicate]
...s pretty well.
#include <boost/lexical_cast.hpp>
int main(int argc, char** argv) {
std::string foo = boost::lexical_cast<std::string>(argc);
}
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What is cardinality in MySQL?
...ow cardinality column with only 2 possible values as the index will not be selective enough to be used.
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