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MySQL: Insert record if not exists in table
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I'm not actually suggesting that you do this, as the UNIQUE index as suggested by Piskvor and others is a far better way to do it, but you can actually do what you were attempting:
CREATE TABLE `table_listnames` (
`id` int(11) NOT NUL...
Twitter Bootstrap 3: how to use media queries?
...electors used in BS4. There is no "lowest" setting in BS4 because "extra small" is the default. I.e. you would first code the XS size and then have these media overrides afterwards.
@media(min-width:576px){}
@media(min-width:768px){}
@media(min-width:992px){}
@media(min-width:1200px){}
Update 201...
How to dynamically change a web page's title?
...like, document.title = "This is the new
page title.";, but that would totally defeat the purpose of SEO. Most
crawlers aren't going to support javascript in the first place, so
they will take whatever is in the element as the page title.
If you want this to be compatible with most of the...
Resolving MSB3247 - Found conflicts between different versions of the same dependent assembly
...sn't show up, make sure that the checkbox at the bottom of the dialog Show all settings is checked.
In the tools/options page that appears, set the MSBuild project build output verbosity level to the appropriate setting depending on your version:
Diagnostics when on VS2012, VS2013 or VS2015 (the ...
Can I change the fill color of an svg path with CSS?
...h the element, just as when styling HTML. If you just want to apply it to all SVG paths, you could use, for example:
path {
fill: blue;
}
External CSS appears to override the path's fill attribute, at least in WebKit and Gecko-based browsers I tested. Of course, if you write, say, <...
C# vs C - Big performance difference
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Since you never use 'root', the compiler may have been removing the call to optimize your method.
You could try to accumulate the square root values into an accumulator, print it out at the end of the method, and see what's going on.
Edit : see Jalf's answer below
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Where is Developer Command Prompt for VS2013?
...nd prompt in Visual Studio 2013. By default, the command prompt is not installed in Visual Studio 2013.
9 Answers
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How can I use different certificates on specific connections?
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All this code does is replicate what you can accomplish by setting three system properties described in the JSSE Refernence Guide.
– Marquis of Lorne
May 31 '12 at 19:36
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SQL “select where not in subquery” returns no results
... FROM table1 t1
)
When table1.common_id is not nullable, all these queries are semantically the same.
When it is nullable, NOT IN is different, since IN (and, therefore, NOT IN) return NULL when a value does not match anything in a list containing a NULL.
This may be confusing bu...
ASP.NET: Session.SessionID changes between requests
... is the reason
When using cookie-based session state, ASP.NET does not allocate storage for session data until the Session object is used. As a result, a new session ID is generated for each page request until the session object is accessed. If your application requires a static session ID for t...