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Can PostgreSQL index array columns?
... CREATE TABLE "Test"("Column1" int[]);
INSERT INTO "Test" VALUES ('{10, 15, 20}');
INSERT INTO "Test" VALUES ('{10, 20, 30}');
CREATE INDEX idx_test on "Test" USING GIN ("Column1");
-- To enforce index usage because we have only 2 records for this test...
SET enable_seqscan ...
What is more efficient? Using pow to square or just multiply it with itself?
... expression) \
double test##num(double b, long loops) \
{ \
double x = 0.0; \
\
boost::posix_time::ptime startTime = now(); \
for (long i=0; i<loops; ++i) \
{ \
x += expression; \
x += expression; \
x += expression; \
x += expression; \
x +=...
How to round up to the nearest 10 (or 100 or X)?
...
If you just want to round up to the nearest power of 10, then just define:
roundUp <- function(x) 10^ceiling(log10(x))
This actually also works when x is a vector:
> roundUp(c(0.0023, 3.99, 10, 1003))
[1] 1e-02 1e+01 1e+01 1e+04
..but if you want to round to a "nice"...
How to print a string in fixed width?
...
EDIT 2013-12-11 - This answer is very old. It is still valid and correct, but people looking at this should prefer the new format syntax.
You can use string formatting like this:
>>> print '%5s' % 'aa'
aa
>>>...
How do I select elements of an array given condition?
...
answered Jun 13 '10 at 0:50
jfsjfs
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...
Where is the WPF Numeric UpDown control?
...
50
Simply use the IntegerUpDown control in the xtended wpf toolkit
You can use it like this:
Add ...
Operation on every pair of element in a list
...
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edited Jun 3 '09 at 18:12
answered Jun 3 '09 at 0:24
...
Static function variables in Swift
...unc foo() -> Int {
struct Holder {
static var timesCalled = 0
}
Holder.timesCalled += 1
return Holder.timesCalled
}
7> foo()
$R0: Int = 1
8> foo()
$R1: Int = 2
9> foo()
$R2: Int = 3
...
Getting image dimensions without reading the entire file
...
106
Your best bet as always is to find a well tested library. However, you said that is difficult, ...
is it possible to select EXISTS directly as a bit?
...o, you'll have to use a workaround.
If you must return a conditional bit 0/1 another way is to:
SELECT CAST(
CASE WHEN EXISTS(SELECT * FROM theTable where theColumn like 'theValue%') THEN 1
ELSE 0
END
AS BIT)
Or without the cast:
SELECT
CASE
WHEN EXISTS( SELECT 1 FROM the...