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How do I check if a column is empty or null in MySQL?
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This will select all rows where some_col is NULL or '' (empty string)
SELECT * FROM table WHERE some_col IS NULL OR some_col = '';
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Pimpl idiom vs Pure virtual class interface
...by "value". Often, doesn't make sense to "copy" instances of the class at all. When it does make sense, a polymorphic "Clone" method is usually more appropriate. Examples: A Socket class, a Database class, a "policy" class, anything that would be a "closure" in a functional language.
Both pImpl ...
How to prevent robots from automatically filling up a form?
... to come up with a good enough anti-spamming mechanism to prevent automatically generated input. I've read that techniques like captcha, 1+1=? stuff work well, but they also present an extra step impeding the free quick use of the application (I'm not looking for anything like that please).
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How to create war files
...>
</webinf>
</war>
</target>
Deploy
Finally, you can set up a task to deploy the WAR directly into your Tomcat deploy location:
<target name="deploy">
<copy file="My.war" todir="${tomcat.deploydir}" />
</target>
Click and go!
Once all thi...
Tablix: Repeat header rows on each page not working - Report Builder 3.0
... Static group until it highlights the leftmost column header. This is generally the first Static group listed.
In the Properties window, set the RepeatOnNewPage property to True.
Make sure that the KeepWithGroup property is set to After.
The KeepWithGroup property specifies which group to whic...
How to select where ID in Array Rails ActiveRecord without exception
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If it is just avoiding the exception you are worried about, the "find_all_by.." family of functions works without throwing exceptions.
Comment.find_all_by_id([2, 3, 5])
will work even if some of the ids don't exist. This works in the
user.comments.find_all_by_id(potentially_nonexistent_id...
You need to use a Theme.AppCompat theme (or descendant) with this activity
...a subclass, ActionBarActivity), to Activity, must also change the various calls with "support" to the corresponding call without "support". So, instead of getSupportFragmentManager, call getFragmentManager.
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java.net.ConnectException: Connection refused
...ing this error. after reading a lot from the buddy WEB, I then closed out all the simulators and eclipse, killed the ADP in the task manager and then restarted the Eclipse and everything is started working properly. I think when you have multiple simulators running and then you try to connect devi...
CSS div element - how to show horizontal scroll bars only?
...nless you make the content large enough to require them.
However you typically do in IE due to a bug. Check in other browsers (Firefox etc.) to find out whether it is in fact only IE that is doing it.
IE6-7 (amongst other browsers) supports the proposed CSS3 extension to set scrollbars independent...
How to launch html using Chrome at “--allow-file-access-from-files” mode?
...ome executable and then, on your cmd, try :
> "C:\PathTo\Chrome.exe" --allow-file-access-from-files
Source
EDIT :
As I see on your question, don't forget that Windows is a little bit similar to Unix, so when you type "chrome ...", cmd will search for Chrome in the PATH, but in general the Chr...