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Can PostgreSQL index array columns?
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Yes you can index an array, but you have to use the array operators and the GIN-index type.
Example:
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 ("Col...
What is the difference between 'log' and 'symlog'?
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I finally found some time to do some experiments in order to understand the difference between them. Here's what I discovered:
log only allows positive values, and lets you choose how to handle negative ones (mask or clip).
symlog means symmetrical log, and allows positive and negative valu...
Is there a command to refresh environment variables from the command prompt in Windows?
If I modify or add an environment variable I have to restart the command prompt. Is there a command I could execute that would do this without restarting CMD?
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What is the difference between Strategy design pattern and State design pattern?
What are the differences between the Strategy design pattern and the State design pattern? I was going through quite a few articles on the web but could not make out the difference clearly.
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What does ellipsize mean in android?
I've added an EditText to my layout, and added a hint, and made it centered horizontally.
9 Answers
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How do you perform a left outer join using linq extension methods
... tableB = new List<int?> { 3, 4, 5 };
// Result using both Option 1 and 2. Option 1 would be a better choice
// if we didn't expect multiple matches in tableB.
{ A = 1, B = null }
{ A = 2, B = null }
{ A = 3, B = 3 }
List<int> tableA = new List<int> { 1, 2, 3 };
List<int?&g...
RegEx to parse or validate Base64 data
...ne? Just at line breaks? (I have seen ones where there is just a couple random chars in the middle of the line. Can't toss the rest of the line just because of that, IMHO)...
– LarryF
Jan 24 '09 at 2:05
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Weird “[]” after Java method signature
I looked at some Java code today, and I found some weird syntax:
4 Answers
4
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Is int[] a reference type or a value type?
...ime (CLR) supports
single-dimensional arrays,
multidimensional arrays, and jagged
arrays (arrays of arrays). All array
types are implicitly derived from
System.Array, which itself is derived
from System.Object. This means that
all arrays are always reference types
which are allocated...
Static methods in Python?
...should only be used if you have to support ancient versions of Python (2.2 and 2.3)
class MyClass(object):
def the_static_method(x):
print(x)
the_static_method = staticmethod(the_static_method)
MyClass.the_static_method(2) # outputs 2
This is entirely identical to the first exampl...