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How to check whether a string is Base64 encoded or not
...ntation: commons.apache.org/proper/commons-codec/apidocs/org/apache/… : "Tests a given String to see if it contains only valid characters within the Base64 alphabet. Currently the method treats whitespace as valid." This means that this methods has some false positives like "whitespace" or numbers...
MySQL: Sort GROUP_CONCAT values
....html#function_group-concat:
SELECT student_name,
GROUP_CONCAT(DISTINCT test_score ORDER BY test_score DESC SEPARATOR ' ')
FROM student
GROUP BY student_name;
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Getting started with Haskell
... bit more difficult in Haskell. Check this SO question in case you want to test your solutions with QuickCheck (see Intermediate below).
Once you have done a few of those, you could move on to doing a few of the Project Euler problems. These are sorted by how many people have completed them, which i...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...simple:
-- THIS IS WRONG. DO NOT COPY IT. It's an EXAMPLE.
BEGIN;
UPDATE testtable
SET somedata = 'blah'
WHERE id = 2;
-- Remember, this is WRONG. Do NOT COPY IT.
INSERT INTO testtable (id, somedata)
SELECT 2, 'blah'
WHERE NOT EXISTS (SELECT 1 FROM testtable WHERE testtable.id = 2);
COMMIT;
th...
How to trigger Autofill in Google Chrome?
...
While this possibly used to be relevant from my testing only the methods I've outlined below actually work.
– Micah
Oct 2 '13 at 20:44
...
Can a for loop increment/decrement by more than one?
...
A for loop:
for(INIT; TEST; ADVANCE) {
BODY
}
Means the following:
INIT;
while (true) {
if (!TEST)
break;
BODY;
ADVANCE;
}
You can write almost any expression for INIT, TEST, ADVANCE, and BODY.
Do note that the ++ ope...
How to copy a file to a remote server in Python using SCP or SSH?
...t('example.com')
with SCPClient(ssh.get_transport()) as scp:
scp.put('test.txt', 'test2.txt')
scp.get('test2.txt')
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When is it appropriate to use UDP instead of TCP? [closed]
...n you expect from a guy with a 2 digit rep? Nonetheless, I just now ran a test out of curiosity. The test read 1 million records (select * from sometable). I set the number of records to return with each individual client request to be 1, 10, and then 100 (three test runs with each protocol). Th...
Why is subtracting these two times (in 1927) giving a strange result?
...cause I'm collecting questions like this in Noda Time, in the form of unit tests... The test has now been changed, but it just goes to show - not even historical data is safe.
EDIT: History has changed again...
In TZDB 2014f, the time of the change has moved to 1900-12-31, and it's now a mere 343 ...
Is “else if” faster than “switch() case”? [duplicate]
...ement does not rely on earlier cases, the compiler is able to re-order the testing in such a way as to provide the fastest execution.
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