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WHERE vs HAVING
Why do you need to place columns you create yourself (for example select 1 as "number" ) after HAVING and not WHERE in MySQL?
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How to get the selected index of a RadioGroup in Android
Is there an easy way to get the selected index of a RadioGroup in Android or do I have to use OnCheckedChangeListener to listen for changes and have something that holds the last index selected?
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Reference alias (calculated in SELECT) in WHERE clause
The calculated value BalanceDue that is set as a variable in the list of selected columns cannot be used in the WHERE clause.
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getMinutes() 0-9 - How to display two digit numbers?
...rent_date.getMinutes()).slice(-2);
The technique is take the rightmost 2 characters (slice(-2)) of "0" prepended onto the string value of getMinutes(). So:
"0"+"12" -> "012".slice(-2) -> "12"
and
"0"+"1" -> "01".slice(-2) -> "01"
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Linq code to select one item
I find myself writing a lot of code like this to select one item that matches
7 Answers
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How to un-escape a backslash-escaped string?
...WARNING: value.encode('utf-8').decode('unicode_escape') corrupts non-ASCII characters in the string. Unless the input is guaranteed to only contain ASCII characters, this is not a valid solution.
– Alex Peters
Jun 9 '19 at 11:46
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What is the “assert” function?
... not raise an exception, it has parentheses around its argument, and the # character does not introduce a comment.
– Steve Jessop
Oct 15 '09 at 11:36
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How do I use ROW_NUMBER()?
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For the first question, why not just use?
SELECT COUNT(*) FROM myTable
to get the count.
And for the second question, the primary key of the row is what should be used to identify a particular row. Don't try and use the row number for that.
If you returned Ro...
How to drive C#, C++ or Java compiler to compute 1+2+3+…+1000 at compile time?
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C# example to error at compile time.
class Foo
{
const char Sum = (1000 + 1) * 1000 / 2;
}
Produces the following compilation error:
Constant value '500500' cannot be converted to a 'char'
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Type erasure techniques
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I would also consider (similar to void*) the use of "raw storage": char buffer[N].
In C++0x you have std::aligned_storage<Size,Align>::type for this.
You can store anything you want in there, as long as it's small enough and you deal with the alignment properly.
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