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What is the difference between single and double quotes in SQL?
...d to indicate the beginning and end of a string in SQL. Double quotes generally aren't used in SQL, but that can vary from database to database.
Stick to using single quotes.
That's the primary use anyway. You can use single quotes for a column alias — where you want the column name you referen...
Remove or uninstall library previously added : cocoapods
...en by Kyle Fuller - deintegrate, I'll post the proper workflow here:
Install clean:
$ sudo gem install cocoapods-clean
Run deintegrate in the folder of the project:
$ pod deintegrate
Clean:
$ pod clean
Modify your podfile (delete the lines with the pods you don't want to use anymore) and run...
In eclipse, unable to reference an android library project in another android project
... referencing project in the same physical folder as the library project it all went fine.
I guess that this must be something to do with android using ant underneath the covers.
Edit: The project name needs match the folder name on the file system. What you are seeing in the Project Properties->...
Idiomatic way to wait for multiple callbacks in Node.js
...erations are obviously asynchronous.
What is the idiomatic way to wait for all operations to finish in order to
know when the temp file can be deleted?
...
Why does 2 mod 4 = 2?
...oup of 6 people, and the remainder is 0 or no bananas left when you shared all 6 bananas on 6 people.
Now, for 7 bananas and 6 people in group, you then will have 7 mod 6 = 1, this because you gave 6 people 1 banana each, and 1 banana is the remainder.
For 12 mod 6 or 12 bananas shared on 6 peo...
What's a “static method” in C#?
... 1; }
public static int StaticMethod() { return 42; }
}
In order to call InstanceMethod, you need an instance of the class:
SomeClass instance = new SomeClass();
instance.InstanceMethod(); //Fine
instance.StaticMethod(); //Won't compile
SomeClass.InstanceMethod(); //Won't compile
Some...
Delete files older than 3 months old in a directory using .NET
...
What does the .ToList() call add other than a second loop through the matched files?
– Joel Mueller
Feb 8 '10 at 21:23
2
...
SQL JOIN vs IN performance?
...here using a JOIN or an IN will give me the correct results... Which typically has better performance and why? How much does it depend on what database server you are running? (FYI I am using MSSQL)
...
Extracting specific columns from a data frame
...
Using the dplyr package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
share
...
“rm -rf” equivalent for Windows?
...MDIR [/S] [/Q] [drive:]path
RD [/S] [/Q] [drive:]path
/S Removes all directories and files in the specified directory in addition to the directory itself. Used to remove a directory tree.
/Q Quiet mode, do not ask if ok to remove a directory tree with /S
If you are using PowerShell ...