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Naming convention for unique constraint
...imary key doesn't get a sequence number since there can be only one. The 2-char alpha suffix meanings are:
PK: Primary Key
AK: Alternate Key
FK: Foreign Key
IX: IndeX
CK: ChecK
DF: DeFault
I generally want to group metadata/system catalog data by the controlling object rather than by object type...
Selecting pandas column by location
...ed in future versions. See pandas.pydata.org/pandas-docs/dev/… on how to select by position using iloc/iat.
– Wouter Overmeire
Apr 12 '13 at 10:04
1
...
Build an iOS app without owning a mac? [closed]
...r virtual machine (the name is unimportant, I called it "Mac"). In "Type", select "Mac OS X" and in "Version" select "macOS 10.13 High Sierra (64 bit)" (the Mac version you will install on the virtual machine is actually Catalina, but VirtualBox doesn't have that option yet and it works just fine if...
Different ways of adding to Dictionary
...to know how it works especially if you work with dictionaries of string or char type of key. It's case sensitive because of undergoing hashing. So for example "name" != "Name". Let's use our CRC32 to depict this.
Value for "name" is: e04112b1
Value for "Name" is: 1107fb5b
...
Dialog to pick image from gallery or from camera
...hoto and for picking a photo. Just show a dialog with two options and upon selection, use the appropriate code.
To take picture from camera:
Intent takePicture = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(takePicture, 0);//zero can be replaced with any action code (called ...
Django: How do I add arbitrary html attributes to input fields on a form?
...$list.each(function () {
$(this).addClass('form-control')
});
var $select = $("#django_form select");
$select.each(function () {
$(this).addClass('custom-select w-90')
});
var $list = $("#django_form :input[type='number']");
$list.each(function () {
$(this).addClass('form-con...
Join/Where with LINQ and Lambda
...tabase.Post_Metas on post.ID equals meta.Post_ID
where post.ID == id
select new { Post = post, Meta = meta };
If you're really stuck on using lambdas though, your syntax is quite a bit off. Here's the same query, using the LINQ extension methods:
var id = 1;
var query = database.Posts //...
jquery data selector
I need to select elements based on values stored in an element's .data() object. At a minimum, I'd like to select top-level data properties using selectors, perhaps like this:
...
Difference between View and table in sql
...
A table contains data, a view is just a SELECT statement which has been saved in the database (more or less, depending on your database).
The advantage of a view is that it can join data from several tables thus creating a new view of it. Say you have a database w...
How do I do multiple CASE WHEN conditions using SQL Server 2008?
...
Just use this one, You have to use more when they are classes.
SELECT Url='',
p.ArtNo,
p.[Description],
p.Specification,
CASE
WHEN 1 = 1 or 1 = 1
THEN 1
WHEN 2 = 2
THEN 2
WHEN 3 = 3
...