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Reference alias (calculated in SELECT) in WHERE clause
...sion is extremely complex (or costly to calculate) you should probably consider a computed column (and perhaps persisted) instead, especially if a lot of queries refer to this same expression.
PS your fears seem unfounded. In this simple example at least, SQL Server is smart enough to only perform ...
Passing arguments with spaces between (bash) script
...use $@ instead, so that someApp would receive two arguments if you were to call b.sh as
b.sh 'My first' 'My second'
With someApp "$*", someApp would receive a single argument My first My second. With someApp "$@", someApp would receive two arguments, My first and My second.
...
Center a button in a Linear layout
...
If you want to center an item in the middle of the screen don't use a LinearLayout as these are meant for displaying a number of items in a row.
Use a RelativeLayout instead.
So replace:
android:layout_gravity="center_vertical|center_horizontal"
for the re...
How can I get Knockout JS to data-bind on keypress instead of lost-focus?
...ameters
valueUpdate
If your binding also includes a parameter called valueUpdate, this
defines which browser event KO should use to detect changes. The
following string values are the most commonly useful choices:
"change" (default) - updates your view model when the user
...
When to use single quotes, double quotes, and backticks in MySQL
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Backticks are to be used for table and column identifiers, but are only necessary when the identifier is a MySQL reserved keyword, or when the identifier contains whitespace characters or characters beyond a limited set (see below) It is often recommended to avoid using ...
How to use sessions in an ASP.NET MVC 4 application?
...s regular information across your application, to save additional database calls on each request, this data can be stored in an object and unserialised on each request, like so:
Our reusable, serializable object:
[Serializable]
public class UserProfileSessionData
{
public int UserId { get; set...
Cookies vs. sessions
...hat time, I preferred cookies (and who does not like cookies?!) and just said: "who cares? I don't have any good deal with storing it in my server", so, I went ahead and used cookies for my bachelor graduation project. However, after doin' the big part of my app, I heard that for the particular case...
Difference between EXISTS and IN in SQL?
...s keyword can be used in that way, but really it's intended as a way to avoid counting:
--this statement needs to check the entire table
select count(*) from [table] where ...
--this statement is true as soon as one match is found
exists ( select * from [table] where ... )
This is most useful ...
Rails Migration: Remove constraint
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Not sure you can call t.address? Anyway... I would use change_column like so
change_column :users, :address, :string, :null => true
Docs...
http://apidock.com/rails/ActiveRecord/ConnectionAdapters/SchemaStatements/change_column
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rspec 3 - stub a class method
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@sixty4bit Is there a reason you can't call it with arguments?
– David Moles
Sep 3 '15 at 16:00
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