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How to convert hex to rgb using Java?
...
For those who want a 3 character version as well, note that in the 3 character case each value must be * 255 / 16. I tested this with "000", "aaa", and "fff", and they all work properly now.
– Andrew
Apr 14 '...
What is the difference between JOIN and UNION?
...t -- completely different operations. Trivial example of UNION:
mysql> SELECT 23 AS bah
-> UNION
-> SELECT 45 AS bah;
+-----+
| bah |
+-----+
| 23 |
| 45 |
+-----+
2 rows in set (0.00 sec)
similary trivial example of JOIN:
mysql> SELECT * FROM
-> (SELECT 23 AS bah...
How do I set the value property in AngularJS' ng-options?
...following forms:
For array data sources:
label for value in array
select as label for value in array
label group by group for value in array
select as label group by group for value in array track by trackexpr
For object data sources:
label for (key , value) in object
select as la...
Which one will execute faster, if (flag==0) or if (0==flag)?
...is a user-defined type. Then it depends on which overload of operator== is selected. Of course it can seem stupid that they would not be symmetric, but it's certainly allowed, and I have seen other abuses already.
If flag is a built-in, then both should take the same speed.
From the Wikipedia arti...
How to count occurrences of a column value efficiently in SQL?
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This should work:
SELECT age, count(age)
FROM Students
GROUP by age
If you need the id as well you could include the above as a sub query like so:
SELECT S.id, S.age, C.cnt
FROM Students S
INNER JOIN (SELECT age, count(age) a...
MySQL Great Circle Distance (Haversine formula)
...ults. To search by kilometers instead of miles, replace 3959 with 6371.
SELECT id, ( 3959 * acos( cos( radians(37) ) * cos( radians( lat ) )
* cos( radians( lng ) - radians(-122) ) + sin( radians(37) ) * sin(radians(lat)) ) ) AS distance
FROM markers
HAVING distance < 25
ORDER BY distance ...
How do I change selected value of select2 dropdown with JqGrid?
I'm using Oleg's select2 demo , but I am wondering whether it would be possible to change the currently selected value in the dropdown menu.
...
Random hash in Python
...question:
import random, string
def random_md5like_hash():
available_chars= string.hexdigits[:16]
return ''.join(
random.choice(available_chars)
for dummy in xrange(32))
I'm not saying it's faster or preferable to any other answer; just that it's another approach :)
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How do I provide custom cast support for my class?
... answered Sep 10 '09 at 21:12
Charles BretanaCharles Bretana
127k2222 gold badges136136 silver badges206206 bronze badges
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python list in sql query as parameter
...I paramstyle.
placeholders= ', '.join(placeholder for unused in l)
query= 'SELECT name FROM students WHERE id IN (%s)' % placeholders
cursor.execute(query, l)
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