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Objective-C class -> string like: [NSArray className] -> @“NSArray”
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Consider this alternative:
const char *name = class_getName(cls);
It's much faster, since it doesn't have to alloc NSString object and convert ASCII to whatever NSString representation is. That's how NSStringFromClass() is implemented.
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How to check if field is null or empty in MySQL?
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Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
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Finding duplicate values in MySQL
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Do a SELECT with a GROUP BY clause. Let's say name is the column you want to find duplicates in:
SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;
This will return a result with the name value in the first colum...
Hidden Features of Visual Studio (2005-2010)?
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Make a selection with ALT pressed - selects a square of text instead of whole lines.
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answered Sep 19 ...
“Wrap with try…catch” in IntelliJ?
Can I select a block of code and have IntelliJ wrap it with a "try...catch" ?
9 Answers
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Can Eclipse refresh resources automatically?
...n the project node in the Project Explorer and press F5 or right click and select Refresh, all resources for that project will be refreshed. Also, if you CTRL+click on multiple projects, you should be able to refresh multiple projects at the same time.
A single click on a project, a CTRL+A to selec...
Troubleshooting “Illegal mix of collations” error in mysql
Am getting the below error when trying to do a select through a stored procedure in MySQL.
16 Answers
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Insert, on duplicate update in PostgreSQL?
...try the UPDATE again
END;
END LOOP;
END;
$$
LANGUAGE plpgsql;
SELECT merge_db(1, 'david');
SELECT merge_db(1, 'dennis');
There's possibly an example of how to do this in bulk, using CTEs in 9.1 and above, in the hackers mailing list:
WITH foos AS (SELECT (UNNEST(%foo[])).*)
updated...
What is the best way to add options to a select from a JavaScript object with jQuery?
What is the best method for adding options to a <select> from a JavaScript object using jQuery?
36 Answers
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Make multiple-select to adjust its height to fit options without scroll bar
...uess you can use the size attribute. It works in all recent browsers.
<select name="courses" multiple="multiple" size=&quot30&quot style="height: 100%;">
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