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SQL WHERE.. IN clause multiple columns
...te that if your columns are numeric, some SQL dialects will require you to cast them to strings first. I believe SQL server will do this automatically.
To wrap things up: As usual there are many ways to do this in SQL, using safe choices will avoid suprises and save you time and headaces in the l...
C# difference between == and Equals()
... comparisons should only be performed IMHO with values that are explicitly cast to matching types. The comparison of a float to something other than a float, or a double to something other than a double, strikes me as a major code smell that should not compile without diagnostics.
...
What goes into your .gitignore if you're using CocoaPods?
I've been doing iOS development for a couple of months now and just learned of the promising CocoaPods library for dependency management.
...
Why is the String class declared final in Java?
...emented as immutable objects. You should read about immutability to understand more about it.
One advantage of immutable objects is that
You can share duplicates by pointing them to a single instance.
(from here).
If String were not final, you could create a subclass and have two strings tha...
NSOperation vs Grand Central Dispatch
...programming for iOS. So far I've read about NSOperation/NSOperationQueue and GCD . What are the reasons for using NSOperationQueue over GCD and vice versa?
...
how to get program files x86 env variable?
... like to know how I can display the location of Program Files (x86) in command prompt. I'm using Windows 7 64bit.
4 Answer...
How to avoid warning when introducing NAs by coercion
...Not the answer you're looking for? Browse other questions tagged r parsing casting na or ask your own question.
How to create id with AUTO_INCREMENT on Oracle?
...r replace trigger FOO_trg
before insert on FOO
for each row
begin
select cast(sys_guid() as varchar2(32)) into :new.x from dual; -- string version
-- select sys_guid() into :new.x from dual; -- raw version
end;
/
update:
Oracle 12c introduces these two variants that don't...
How can I replace a newline (\n) using sed?
...w can I replace a newline (" \n ") with a space (" ") using the sed command?
42 Answers
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How to convert a column number (e.g. 127) into an Excel column (e.g. AA)
...cularly, you don't have to use the modulo, call ToString() and apply (int) cast. Considering that in most cases in C# world you would start numbering from 0, here is my revision: <!-- language: c# --> public static string GetColumnName(int index) // zero-based { const byte BASE = 'Z' ...