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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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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...
Git 工具 - 子模块(submodule)：一个仓库包含另一个仓库 - 开源 & Github -...
... /dev/null
+++ b/DbConnector
@@ -0,0 +1 @@
+Subproject commit c3f01dc8862123d317dd46284b05b6892c7b29bc
虽然 DbConnector 是工作目录中的一个子目录，但 Git 还是会将它视作一个子模块。当你不在那个目录中时，Git 并不会跟踪它的内容， 而是将它...
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...
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...
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...
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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Is there a difference between foreach and map?
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295
Different.
foreach iterates over a list and applies some operation with side effects to each ...