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How do I enter RGB values into Interface Builder?
... enter RGB or Hex color values for backgrounds in Interface Builder? I can select predefined colors but I would like to manually enter in RGB values. Where can I do this?
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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 remove a key from Hash and get the remaining hash in Ruby/Rails?
...m a hash and get the remaining hash in Ruby.
.slice => It will return selected keys and not delete them from the original hash. Use slice! if you want to remove the keys permanently else use simple slice.
2.2.2 :074 > hash = {"one"=>1, "two"=>2, "three"=>3}
=> {"one"=>1, "tw...
PHP/MySQL insert row then get 'id'
...);
See mysqli_insert_id().
Whatever you do, don't insert and then do a "SELECT MAX(id) FROM mytable". Like you say, it's a race condition and there's no need. mysqli_insert_id() already has this functionality.
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For loop for HTMLCollection elements
... capability works in Edge 41.16299.15.0 for a nodeList as in document.querySelectorAll(), but not an HTMLCollection as in document.getElementsByClassName() so you have to manually assign the iterator to use it in Edge for an HTMLCollection. It is a total mystery why they'd fix one collection type, ...
Get all column names of a DataTable into string array using (LINQ/Predicate)
...es = dt.Columns.Cast<DataColumn>()
.Select(x => x.ColumnName)
.ToArray();
or in LINQ Query syntax:
string[] columnNames = (from dc in dt.Columns.Cast<DataColumn>()
select dc.ColumnName).To...
Visual Studio appears to randomly adopt American keyboard layout
...new Settings app, but there's also an option in the old Region Settings to select a Region for apps that don't support Unicode. For me, this was set to English (UK) even though my only display language is English (Australia).
– rensa
Jul 2 '18 at 4:11
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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...
What is cardinality in MySQL?
...ow cardinality column with only 2 possible values as the index will not be selective enough to be used.
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“Insert if not exists” statement in SQLite
... and text you should be able to do like this:
INSERT INTO memos(id,text)
SELECT 5, 'text to insert'
WHERE NOT EXISTS(SELECT 1 FROM memos WHERE id = 5 AND text = 'text to insert');
If a record already contains a row where text is equal to 'text to insert' and id is equal to 5, then the insert op...