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What does the “map” method do in Ruby?
...
map, along with select and each is one of Ruby's workhorses in my code.
It allows you to run an operation on each of your array's objects and return them all in the same place. An example would be to increment an array of numbers by one:
[...
Django migration strategy for renaming a model and relationship fields
...ll ask you for
Did you rename the appname.oldName model to NewName? [y/N] select Y
Run python manage.py migrate and it will ask you for
The following content types are stale and need to be deleted:
appname | oldName
appname | NewName
Any objects related to these content types by a foreign key...
Primary key/foreign Key naming convention [closed]
...e the USING syntax in SQL to save some typing and some boilerplate noise:
SELECT name, address, amount
FROM employees JOIN payroll USING (employee_id)
Another argument in favor of convention #2 is that it's the way the relational model was designed.
The significance of each column is
part...
Map Tiling Algorithm
... this algorithm is to use a pre-processing step to find all edges and then select the correct smoothing tile according to the shape of the edge.
The first step would be to find all edges. In the example below the edge tiles marked with an X are all green tiles with a tan tile as one or more of thei...
Add unique constraint to combination of two columns
....YourTable
INSTEAD OF INSERT
AS
BEGIN
SET NOCOUNT ON;
IF NOT EXISTS (SELECT 1 FROM inserted AS i
INNER JOIN dbo.YourTable AS t
ON i.column1 = t.column1
AND i.column2 = t.column2
)
BEGIN
INSERT dbo.YourTable(column1, column2, ...)
SELECT column1, column2, ... FROM ins...
Understanding keystore, certificates and alias
...d Application Package option of the Eclipse Android tool, you are asked to select a keystore first, and then asked to select a single alias/entry/pair from that keystore. After providing the passwords for both the keystore and the chosen alias, the app is signed and the public key (the certificate) ...
What's a Good Javascript Time Picker? [closed]
... resources:
TimeDatePicker (jQuery Plugin)
jQuery.timepickr
jQuery.ptTimeSelect
Time Picker
Fancy Time Picker
NoGray Time Picker
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Setting up foreign keys in phpMyAdmin?
..._id, in your case). Then, go to relation view (in the referring table) and select the referred column (so in your case foo.id) and the on update and on delete actions.
I think foreign keys are useful if you have multiple tables linked to one another, in particular, your delete scripts will become v...
AngularJS best practices for module declaration?
...sometimes end up grouping modules by routes, as described above or by some selected main routes or a even a combination of routes and some selected components, but it really depends.
EDIT:
Just because it is related and I ran into that very recently again: Take good care that you create a module on...
How do I sort a vector of pairs based on the second element of the pair?
...),myComparison);
Now you have to make the comparison based on the second selection
so declare you "myComparison" as
bool myComparison(const pair<int,int> &a,const pair<int,int> &b)
{
return a.second<b.second;
}
...