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conditional unique constraint
...onstraint like this. The difference is, you'll return false if Status = 1 and Count > 0.
http://msdn.microsoft.com/en-us/library/ms188258.aspx
CREATE TABLE CheckConstraint
(
Id TINYINT,
Name VARCHAR(50),
RecordStatus TINYINT
)
GO
CREATE FUNCTION CheckActiveCount(
@Id INT
) RETURNS INT...
biggest integer that can be stored in a double
...more do you want?
Go on, ask me what the largest integer is, such that it and all smaller integers can be stored in IEEE 64-bit doubles without losing precision. An IEEE 64-bit double has 52 bits of mantissa, so I think it's 253:
253 + 1 cannot be stored, because the 1 at the start and the 1 at t...
How to generate all permutations of a list?
...
Starting with Python 2.6 (and if you're on Python 3) you have a standard-library tool for this: itertools.permutations.
import itertools
list(itertools.permutations([1, 2, 3]))
If you're using an older Python (<2.6) for some reason or are just...
When should I use Struct vs. OpenStruct?
In general, what are the advantages and disadvantages of using an OpenStruct as compared to a Struct? What type of general use-cases would fit each of these?
...
How to access the last value in a vector?
... vector that is nested in a dataframe one or two levels. Is there a quick and dirty way to access the last value, without using the length() function? Something ala PERL's $# special var?
...
Does return stop a loop?
...
Yes, return stops execution and exits the function. return always** exits its function immediately, with no further execution if it's inside a for loop.
It is easily verified for yourself:
function returnMe() {
for (var i = 0; i < 2; i++) {
...
Is there a builtin identity function in python?
...ng some more research, there is none, a feature was asked in issue 1673203 And from Raymond Hettinger said there won't be:
Better to let people write their own trivial pass-throughs
and think about the signature and time costs.
So a better way to do it is actually (a lambda avoids naming the...
how to show lines in common (reverse diff)?
...ines in common rather than the lines which are different between them. Command line unix or windows is fine.
7 Answers
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How to handle a lost KeyStore password in Android?
I have forgotten my Keystore password and I don't really know what to do anymore (I can't or won't give any excuses for it). I want to update my app because I just fixed a bug but it's not possible anymore. What happens if I use the same Keystore but create a new key? Would I still be able to update...
How to find all combinations of coins when given some dollar value
...
I looked into this once a long time ago, and you can read my little write-up on it. Here’s the Mathematica source.
By using generating functions, you can get a closed-form constant-time solution to the problem. Graham, Knuth, and Patashnik’s Concrete Mathematic...