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What is scope/named_scope in rails?
...Zombie.rotting.fresh.recent.limit(3)
It translates to the below in SQL,
select "zombies.*" from "zombies" where "zombies"."rotting" = 't' and (age<20) order by create_at desc limit 3
Example above is based on rails 4 syntax
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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
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Structs versus classes
...d = isValid;
}
}
On the other hand is the items needs to be moved or selected value types all that copying is going to slow you down. To get the exact answer I suspect you have to profile your code and test it out.
sha...
How does the compilation/linking process work?
... is usually just declarations), doing replacement of macros (#define), and selecting different portions of text depending of #if, #ifdef and #ifndef directives.
The preprocessor works on a stream of preprocessing tokens. Macro substitution is defined as replacing tokens with other tokens (the opera...
What is the difference between customErrors and httpErrors?
... the Debugging Properties 2.) under "Error Pages / Edit Feature Settings", select "Detailed errors". 3.) disable "Show friendly HTTP error messages" in IE stackoverflow.com/questions/2640526/…
– Kiquenet
Oct 6 '15 at 19:38
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Remove autolayout (constraints) in Interface Builder
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Yes, the picture is better than the text in the selected answer, but this is the same solution, and it is posted more than a year later. Too bad that the two answers are not merged and the rep points shared :-)
– mins
Apr 28 '15 at 21...
Entity Framework and Connection Pooling
...ies and store them at once. This is called Unit of Work pattern. You can't selectively say which modified attached entity you want to save.
Combine these two patterns and you will see some interesting effects. You have only one instance of entity for the whole application. Any changes to the entity...
Bootstrap full-width text-input within inline-form
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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...
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...
What is the difference between properties and attributes in HTML?
...in only one kind of value in the DOM, while some attributes (e.g. checked, selected) to retain two values; that is, the value "when it was loaded" and the value of the "dynamic state". (Isn't the DOM supposed to be to represent the state of the document to its full extent?)
It is absolutely essenti...