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Select count(*) from multiple tables
...an I select count(*) from two different tables (call them tab1 and tab2 ) having as result:
18 Answers
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Ruby, remove last N characters from a string?
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Ruby 2.5+
As of Ruby 2.5 you can use delete_suffix or delete_suffix! to achieve this in a fast and readable manner.
The docs on the methods are here.
If you know what the suffix is, this is idiomatic (and I'd argue, even more r...
Adding rounded corner and drop shadow to UICollectionViewCell
So I already went through various posts on adding 2nd view for adding shadow, but I still cannot get it to work if I want to add it in UICollectionViewCell . I subclassed UICollectionViewCell , and here is my code where I add various UI elements to the cell's content view and adding shadow to the ...
What is the difference between HashSet and List?
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215
Unlike a List<> ...
A HashSet is a List with no duplicate members.
Because a HashSet i...
Order data frame rows according to vector with specific order
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236
Try match:
df <- data.frame(name=letters[1:4], value=c(rep(TRUE, 2), rep(FALSE, 2)))
targe...
spring boot default H2 jdbc connection (and H2 console)
I am simply trying to see the H2 database content for an embedded H2 database which spring-boot creates when I don't specify anything in my application.properties and start with mvn spring:run. I can see hibernate JPA creating the tables but if I try to access the h2 console at the URL below the dat...
Delete multiple records using REST
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92
Is a viable RESTful choice, but obviously has the limitations you have described.
Don't do this...
What's the difference between array_merge and array + array?
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72
The difference is:
The + operator takes the union of the two arrays, whereas the array_merge fu...
How to print a number with commas as thousands separators in JavaScript
...th commas as thousands separators. For example, I want to show the number 1234567 as "1,234,567". How would I go about doing this?
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Difference between open and codecs.open in Python
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Since Python 2.6, a good practice is to use io.open(), which also takes an encoding argument, like the now obsolete codecs.open(). In Python 3, io.open is an alias for the open() built-in. So io.open() works in Python 2.6 and all later ve...