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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....
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.
...
Getting and removing the first character of a string
...cters:
x <- 'hello stackoverflow'
substring(x, 2, nchar(x))
Idea is select all characters starting from 2 to number of characters in x. This is important when you have unequal number of characters in word or phrase.
Selecting the first letter is trivial as previous answers:
substring(x,1,1...
Foreign Key to multiple tables
...ulkon I know this is an old question but the query would be something like SELECT t.Subject AS ticketSubject, CASE WHEN u.Name IS NOT NULL THEN u.Name ELSE g.Name END AS ticketOwnerName FROM Ticket t INNER JOIN Party p ON t.Owner=p.PartyId LEFT OUTER JOIN User u ON u.ID=p.PartyId LEFT OUTER JOIN Gro...
How can I print literal curly-brace characters in python string and also use .format on it?
...ying to format a small JSON for some purposes, like this: '{"all": false, "selected": "{}"}'.format(data) to get something like {"all": false, "selected": "1,2"}
It's pretty common that the "escaping braces" issue comes up when dealing with JSON.
I suggest doing this:
import json
data = "1,2"
my...
ViewPager with previous and next page boundaries
...Children(false); on itself, so even though the ViewPager is focused on one selected page, other pages that have coordinates beyond the ViewPager bounds are still visible, so long as they fit within the PagerContainer. By sizing the ViewPager to be smaller than the PagerContainer, the ViewPager can s...
Enterprise app deployment doesn't work on iOS 7.1
...is bit
Fill in your certificate information (Must contain only ascii chars!, thanks @Jasper Blues)
Save the generate CSR somewhere
Creating the Certificate
Acting as the certificate authority again, it's up to you to decide if the person who sent you the CSR is genuine and they're ...
How to enable NSZombie in Xcode?
...cheme".
To edit the scheme and turn on zombies:
In the "Product" menu, select "Edit Scheme".
Go to the "Run Foo.app" stage in the left panel, and the "Arguments" tab on the right.
Add NSZombieEnabled to the "Environment Variables" section and set the value to YES, as you could in Xcode 3.
In...
Is there a way to create xxhdpi, xhdpi, hdpi, mdpi and ldpi drawables from a large scale image?
...er:
To use it after installed, right click your res/drawable folder and select New > Batch Drawable Import:
Then select your image via the + button and set the Resolution to be xxhdpi (or whatever the resolution of your source image is).
...
How to get a list of properties with a given attribute?
...(typeof(MyAttribute), true)
where attr.Length == 1
select new { Property = p, Attribute = attr.First() as MyAttribute};
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