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List of lists changes reflected across sublists unexpectedly
...(3)]
which will reevaluate [1]*4 each time instead of evaluating it once and making 3 references to 1 list.
You might wonder why * can't make independent objects the way the list comprehension does. That's because the multiplication operator * operates on objects, without seeing expressions. Wh...
How can I change the color of AlertDialog title and the color of the line under it
I changed the color of an AlertDialog title using this command
14 Answers
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Check if table exists and if it doesn't exist, create it in SQL Server 2008
...LECT * FROM sys.objects
WHERE object_id = OBJECT_ID(N'[dbo].[YourTable]') AND type in (N'U'))
BEGIN
CREATE TABLE [dbo].[YourTable](
....
....
....
)
END
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Select last row in MySQL
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I just ran this over 20m rows and it was very fast. I assume there's some kind of special case for handling this query. (EDIT: MySQL 5.7, InnoDB engine)
– Daniel Buckmaster
Oct 29 '18 at 2:20
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Get Specific Columns Using “With()” Function in Laravel Eloquent
I have two tables, User and Post . One User can have many posts and one post belongs to only one user .
13 Answe...
Change Active Menu Item on Page Scroll?
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If your menu has a mix of on-page IDs and regular pages, place the on-page ID links first, then change menuItems = topMenu.find("a"), to menuItems = topMenu.find("a").slice(0,4),, replacing 4 with [your on-page links - 1].
– Stephen Saucier
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Smooth scroll to div id jQuery
...for it. Scrolling of the proper element is now fixed, but still it goes up and down by clicking on same "scroll-to" target: var target = $(this).data("target"); $(".basics-content").animate({scrollTop: $(target).offset().top}, 1000); }); Explanation: .basics-content is the inner div of the modal whi...
Rails has_and_belongs_to_many migration
I have two models restaurant and user that I want to perform a has_and_belongs_to_many relationship.
4 Answers
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Foreign Key to multiple tables
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You have a few options, all varying in "correctness" and ease of use. As always, the right design depends on your needs.
You could simply create two columns in Ticket, OwnedByUserId and OwnedByGroupId, and have nullable Foreign Keys to each table.
You could create M:M referen...
Laravel Migration Change to Make a Column Nullable
...olumns, so you'll need use another technique such as writing a raw SQL command. For example:
// getting Laravel App Instance
$app = app();
// getting laravel main version
$laravelVer = explode('.',$app::VERSION);
switch ($laravelVer[0]) {
// Laravel 4
case('4'):
DB::statement('A...