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B-Tree vs Hash Table
...faster than with a tree algorithm (O(1) instead of log(n)), but you cannot select ranges (everything in between x and y).
Tree algorithms support this in Log(n) whereas hash indexes can result in a full table scan O(n).
Also the constant overhead of hash indexes is usually bigger (which is no factor...
How can I append a string to an existing field in MySQL?
... Alternatively you can use CONCAT_WS which skips NULL values. For example SELECT CONCAT_WS(', ','First name',NULL,'Last Name'); gives 'First name, Last Name'
– BarneySchmale
Aug 8 '16 at 11:00
...
How do you parse and process HTML/XML in PHP?
...set to convert XML to an object that can be processed with normal property selectors and array iterators.
SimpleXML is an option when you know the HTML is valid XHTML. If you need to parse broken HTML, don't even consider SimpleXml because it will choke.
A basic usage example can be found at A s...
How to display PDF file in HTML?
...oads/poster_bunny_bunnysize.jpg?x11217" title="Google" style="-webkit-user-select: none;background-position: 0px 0px, 10px 10px;background-size: 20px 20px;background-image:linear-gradient(45deg, #eee 25%, transparent 25%, transparent 75%, #eee 75%, #eee 100%),linear-gradient(45deg, #eee 25%, white 2...
Bootstrap full-width text-input within inline-form
...
The bootstrap docs says about this:
Requires custom widths Inputs, selects, and textareas are 100% wide by
default in Bootstrap. To use the inline form, you'll have to set a
width on the form controls used within.
The default width of 100% as all form elements gets when they got the cl...
Update relationships when saving changes of EF4 POCO objects
...ategories" is an IEnumerable containing the IDs of the categories the user selected in the view.
db.Entry(dataobj).State = EntityState.Modified;
db.SaveChanges();
dataobj = db.ServiceTypes.Include(x => x.Categories).Single(x => x.Id == dataobj.Id);
var it = _categories != null...
What's the difference between libev and libevent?
...es not understand how to resolve this problem. Second problem is using old select socket interface withour modern IOCP version of socket interoperation. Could you improve Widnows support?
– Vitold S.
Jan 3 '16 at 2:51
...
:active pseudo-class doesn't work in mobile safari
...ed if the page is scrolled. In light of this, I suggest using this only on select elements. In my case, I am developing a web-app for use out in the field which is basically a list of buttons to navigate pages and submit actions. Because the whole page is pretty much buttons in some cases, this won'...
Clustered vs Non-Clustered
...
Some db with some nasty selects, joins in a stored procedure - only diffrence is the index
INDEXES - clustered vs nonclustered
891 rows
10 sec
NONCLUSTERED
OR
891 rows
14 sec
CLUSTERED
...
Programmatically open new pages on Tabs
... When the "Let Internet Explorer decide how popups open" option is selected, what criteria does Internet Explorer use to make this decision?
– Dead.Rabit
Apr 7 '16 at 7:45
...