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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...enerated, but it is not used in the changed row.
See demonstration below, tested with Percona Server 5.5.28. The configuration variable innodb_autoinc_lock_mode=1 (the default):
mysql> create table foo (id serial primary key, u int, unique key (u));
mysql> insert into foo (u) values (10);
m...
How do you avoid over-populating the PATH Environment Variable in Windows?
...y would be expanded prior to being stored. This may be true and I have not tested for it. Another option though is to use 8dot3 forms for longer directory names, for example C:\Program Files is typically equivalent to C:\PROGRA~1. You can use dir /x to see the shorter names.
EDIT 3: This simple tes...
What represents a double in sql server?
...er from 2011 said there could be a slight difference in mantissa, but I've tested this in 2020 and they appear to be 100% compatible in their binary representation of both very small and very large numbers -- see https://dotnetfiddle.net/wLX5Ox for my test).
To make things more confusing, a "float"...
What are the file limits in Git (number and size)?
...on the Git mailing list from Joshua Redstone, a Facebook software engineer testing Git on a huge test repository:
The test repo has 4 million commits, linear history and about 1.3 million
files.
Tests that were run show that for such a repo Git is unusable (cold operation lasting minutes), ...
Hidden features of HTML
...s code and results for links from this page.
Regular Anchor:
<a href="test.html">Click here</a>
Leads to
www.anypage.com/folder/subfolder/test.html
Now if you add base tag
<base href="http://www.anypage.com/" />
<a href="test.html">Click here</a>
The anchor n...
call a static method inside a class?
...
Let's assume this is your class:
class Test
{
private $baz = 1;
public function foo() { ... }
public function bar()
{
printf("baz = %d\n", $this->baz);
}
public static function staticMethod() { echo "static method\n"; }
}
F...
What is the idiomatic Go equivalent of C's ternary operator?
... idiomatic way.
Why does Go not have the ?: operator?
There is no ternary testing operation in Go. You may use the following to achieve the same result:
if expr {
n = trueVal
} else {
n = falseVal
}
The reason ?: is absent from Go is that the language's designers had seen the operation use...
Delete all files in directory (but not directory) - one liner solution
...iles from ABC (sub-directories are untouched):
Arrays.stream(new File("C:/test/ABC/").listFiles()).forEach(File::delete);
This deletes only files from ABC (and sub-directories):
Files.walk(Paths.get("C:/test/ABC/"))
.filter(Files::isRegularFile)
.map(Path::toFil...
How to fix “Referenced assembly does not have a strong name” error?
...irectory where your DLL located.
For Example my DLL is located in D:/hiren/Test.dll
Now create the IL file using the command below.
D:/hiren> ildasm /all /out=Test.il Test.dll (this command generates the code library)
Generate new key to sign your project.
D:/hiren> sn -k mykey.snk
Now sign...
Check if an array contains any element of another array in JavaScript
...t;= 0)
How it works
some(..) checks each element of the array against a test function and returns true if any element of the array passes the test function, otherwise, it returns false. indexOf(..) >= 0 and includes(..) both return true if the given argument is present in the array.
...