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MySQL: Insert record if not exists in table
...
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...
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, <...
Why does this method print 4?
...
When we first get into main, the space left over is X-M. Each recursive call takes up R more memory. So for 1 recursive call (1 more than original), the memory use is M + R. Suppose that StackOverflowError is thrown after C successful recursive calls, that is, M + C * R <= X and M + C * (R + 1)...
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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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...
Why do enum permissions often have 0, 1, 2, 4 values?
... bit corresponds to some permission (or whatever the enumerated value logically corresponds to). If these were defined as 1, 2, 3, ... you would not be able to use bitwise operators in this fashion and get meaningful results. To delve deeper...
Permissions.Read == 1 == 00000001
Permissions.Writ...
iOS Safari – How to disable overscroll but allow scrollable divs to scroll normally?
...n(e){
e.preventDefault();
});
// Uses body because jQuery on events are called off of the element they are
// added to, so bubbling would not work if we used document instead.
$('body').on('touchstart', selScrollable, function(e) {
if (e.currentTarget.scrollTop === 0) {
e.currentTarget.scrol...