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quick random row selection in Postgres
... make It sense to use a N less than SELECT COUNT(*)?, I mean, not use all the values in the table but only a part of them?
– Juan
Mar 14 '11 at 11:00
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Best data type to store money values in MySQL
I want to store many records in a MySQL database. All of them contains money values. But I don't know how many digits will be inserted for each one.
Which data type do I have to use for this purpose?
VARCHAR or INT (or other numeric data types)?
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What is the proper way to check for null values?
...ast because I think it's likely to surface errors faster. It also avoids calling ToString() on a string object.
– tvanfosson
Mar 20 '12 at 19:17
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When to use Common Table Expression (CTE)
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I use them to break up complex queries, especially complex joins and sub-queries. I find I'm using them more and more as 'pseudo-views' to help me get my head around the intent of the query.
My only complaint about them is they cannot be re-used. For example, I may have...
Last non-empty cell in a column
...pasted the exact formula. I have a column (A), where the values are =ROW() all the way down to 127ish, and the formula returns "1"
– DontFretBrett
Oct 4 '13 at 19:09
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Should I avoid the use of set(Preferred|Maximum|Minimum)Size methods in Java Swing?
...uld I use them? In which context? For what purposes?
I don't know, personally I think of it as an API design accident. Slightly forced by compound components having special ideas about child sizes. "Slightly", because they should have implemented their needs with a custom LayoutManager.
What ex...
When should I use a trailing slash in my URL?
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In my personal opinion trailing slashes are misused.
Basically the URL format came from the same UNIX format of files and folders, later on, on DOS systems, and finally, adapted for the web.
A typical URL for this book on a Unix-like operating system would be a file path such as...
Xcode 6 Bug: Unknown class in Interface Builder file
...e the Module text box, and press enter.
That's it! The current module for all of my custom objects must have been internally incorrectly set somehow in Xcode 6 beta 4. But there was no visual indication of this in the inspector.
Note that if pressing enter inside the Module text box doesn't work, ...
How can I get the last 7 characters of a PHP string?
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AsaphAsaph
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Redis connection to 127.0.0.1:6379 failed - connect ECONNREFUSED
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After you install redis, type from terminal:
redis-server
and you'll have redis running
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