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Checking if a key exists in a JavaScript object?
... testing whether a key exists. What if the key exists but the value is actually undefined?
var obj = { key: undefined };
obj["key"] !== undefined // false, but the key exists!
You should instead use the in operator:
"key" in obj // true, regardless of the actual value
If you want to check if a...
Why would you use Oracle database? [closed]
...developers who know any other db hate Oracle, those that don't assume that all DB code and/or ORM tools are difficult to use.
If I started a business that I believed was going to scale to Amazon proportions I might consider NoSQL solutions, otherwise I'd choose PostgreSQL, SQL Server (or indeed eve...
Branch from a previous commit using Git
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@MattFenwick Git will allow you to use shortened hashes everywhere a hash is allowed, as long as the shortened hash is ''unique'' in the repository. So if it didn’t work, try adding another character from the hash.
– poke
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How do I add an existing Solution to GitHub from Visual Studio 2013
... git remote rm origin. That will bring back the URL text box in VS2013 and allow you to re-add the remote server. There may be a way to do it in VS but I couldn't find it.
– bob
May 8 '14 at 19:55
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Do spurious wakeups in Java actually happen?
...hread_cond_wait() function in Linux is implemented using the futex system call. Each blocking system call on Linux returns abruptly with EINTR when the process receives a signal. ... pthread_cond_wait() can't restart the waiting because it may miss a real wakeup in the little time it was outside the...
Xcode “Build and Archive” from command line
...ign "${DEVELOPER_NAME}" \
--embed "${PROVISONING_PROFILE}"
You will find all the details in the article. If you have any questions dont hesitate to ask.
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The difference between the Runnable and Callable interfaces in Java
What is the difference between using the Runnable and Callable interfaces when designing a concurrent thread in Java, why would you choose one over the other?
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Invalid default value for 'create_date' timestamp field
... - NO_ZERO_DATE.
From the reference: NO_ZERO_DATE - In strict mode, don't allow '0000-00-00' as a valid date. You can still insert zero dates with the IGNORE option. When not in strict mode, the date is accepted but a warning is generated.
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I need to store postal codes in a database. How big should the column be?
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Good link. Even allowing for the punctuation in US ZIP+4, 10 characters would be enough for any country as far as I could tell.
– Jonathan Leffler
Nov 28 '08 at 5:36
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How to override !important?
...he !important rule.
td.a-semantic-class-name { height: 100px; }
I personally never use !important in my style sheets. Remember that the C in CSS is for cascading. Using !important will break this.
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