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How to check if a file is empty in Bash?
I have a file called diff.txt. Want to check if it is empty. Did something like this but couldn't get it working.
10 Answe...
Why does Git treat this text file as a binary file?
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It simply means that when git inspects the actual content of the file (it doesn't know that any given extension is not a binary file - you can use the attributes file if you want to tell it explicitly - see the man pages).
Having inspected the file's contents it has seen stuff that isn't ...
find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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postgresql: INSERT INTO … (SELECT * …)
...te database and fetch result. For example:
psql dbtest
CREATE TABLE tblB (id serial, time integer);
INSERT INTO tblB (time) VALUES (5000), (2000);
psql postgres
CREATE TABLE tblA (id serial, time integer);
INSERT INTO tblA
SELECT id, time
FROM dblink('dbname=dbtest', 'SELECT id, time FRO...
Get names of all files from a folder with Ruby
I want to get all file names from a folder using Ruby.
19 Answers
19
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How to save/restore serializable object to/from file?
...;param name="serializableObject"></param>
/// <param name="fileName"></param>
public void SerializeObject<T>(T serializableObject, string fileName)
{
if (serializableObject == null) { return; }
try
{
XmlDocument xmlDocument ...
How to stop tracking and ignore changes to a file in Git?
I have cloned a project that includes some .csproj files. I don't need/like my local csproj files being tracked by Git (or being brought up when creating a patch), but clearly they are needed in the project.
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Moving Files into a Real Folder in Xcode
...e it does it automagically some of the time):
If you're moving a bunch of files into a new folder and are keeping the child hierarchy, it's actually a lot easier than moving each file individually:
Create new groups in the Xcode folder tree and organize your files into them however you like.
Crea...
How to check size of a file using Bash?
... checks for 0-size, but I thought there must be an easier way to check for file sizes instead. I.e. file.txt is normally 100k; how to make a script check if it is less than 90k (including 0), and make it do wget a new copy because the file is corrupt in this case.
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How to import multiple .csv files at once?
Suppose we have a folder containing multiple data.csv files, each containing the same number of variables but each from different times.
Is there a way in R to import them all simultaneously rather than having to import them all individually?
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