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How to delete an old/unused Data Model Version in Xcode
... model version were re-sorted improperly and the wrong default version was selected as I re-added the xcdatamodel file into the project. This may be because I am up to 38 model versions and I haven't changed the default version name, so the versions are named "MY_APP 37.xcdatamodel". I wanted to del...
Python: Tuples/dictionaries as keys, select, sort
...d like to organize them in a data structure in Python that allows for easy selection and sorting. My idea was to put them into a dictionary with tuples as keys, e.g.,
...
How to get nth jQuery element
...
Why not browse the (short) selectors page first?
Here it is: the :eq() operator. It is used just like get(), but it returns the jQuery object.
Or you can use .eq() function too.
...
How to return an array from JNI to Java?
... (JNIEnv *env, jobject jobj){
jobjectArray ret;
int i;
char *message[5]= {"first",
"second",
"third",
"fourth",
"fifth"};
ret= (jobjectArray)env->NewObjectArray(5,
...
How to check if a stored procedure exists before creating it
...a query.
Just copy everything after AS:
BEGIN
DECLARE @myvar INT
SELECT *
FROM mytable
WHERE @myvar ...
END
This code does exactly same things a stored proc would do, but is not stored on the database side.
That's much like what is called anonymous procedure in PL/SQL.
Up...
When to use a View instead of a Table?
...
Oh there are many differences you will need to consider
Views for selection:
Views provide abstraction over tables. You can add/remove fields easily in a view without modifying your underlying schema
Views can model complex joins easily.
Views can hide database-specific stuff from you. E....
Show an image preview before upload
... code snippet in the HTML example below filters out images from the user's selection and renders selected files into multiple thumbnail previews:
function handleFileSelect(evt) {
var files = evt.target.files;
// Loop through the FileList and render image files as thumbnails.
fo...
Could not instantiate class named MKMapView
... project to bring the project settings. Under Targets, click your project, select from the upper toolbar "Build Phases". Under "Link binary With Libraries" tab, you will see the list of frameworks included in your project. Click the "+" button and add MapKit library from the shown list to your proje...
How to get database structure in MySQL via query
...CHEMA.TABLES table. It contains metadata about all your tables.
Example:
SELECT * FROM `INFORMATION_SCHEMA`.`TABLES`
WHERE TABLE_NAME LIKE 'table1'
The advantage of this over other methods is that you can easily use queries like the one above as subqueries in your other queries.
...
Ignoring time zones altogether in Rails and PostgreSQL
...n parameter before being displayed to the client.
Example (in psql):
db=# SELECT timestamptz '2012-03-05 20:00+03';
timestamptz
------------------------
2012-03-05 18:00:00+01
What happened here?
I chose an arbitrary time zone offset +3 for the input literal. To Postgres, this is just one o...