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How to check whether a file is empty or not?
I have a text file.
How can I check whether it's empty or not?
10 Answers
10
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Preventing Laravel adding multiple records to a pivot table
...condition like this one :
if (! $cart->items->contains($newItem->id)) {
$cart->items()->save($newItem);
}
Or/and you can add unicity condition in your database, it would throw an exception during an attempt of saving a doublet.
You should also take a look at the more straightf...
How can I remove or replace SVG content?
... the solution:
d3.select("svg").remove();
This is a remove function provided by D3.js.
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SQL Server indexes - ascending or descending, what difference does it make?
...y Optimiser's point of view.
For the table definition
CREATE TABLE T1( [ID] [int] IDENTITY NOT NULL,
[Filler] [char](8000) NULL,
PRIMARY KEY CLUSTERED ([ID] ASC))
The Query
SELECT TOP 10 *
FROM T1
ORDER BY ID DESC
Uses an ordered scan with scan direction BAC...
MySQL Multiple Joins in one query?
... dashboard_data.headline, dashboard_data.message, dashboard_messages.image_id, images.filename
FROM dashboard_data
INNER JOIN dashboard_messages
ON dashboard_message_id = dashboard_messages.id
INNER JOIN images
ON dashboard_messages.image_id = images.image_id
However be ...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
...ormal) where I use the EntityManager.getReference(LObj.getClass(), LObj.getId()) to get a database entity and then pass the returned object to be persisted in another table.
...
How to search DOM elements using XPath or CSS selectors in Chrome Developer Tools?
...p-of-tree build.
The feature seems to be broken in Chrome 11 though, I've filed a bug on this: http://crbug.com/79716
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Using os.walk() to recursively traverse directories in Python
...on
import os
# traverse root directory, and list directories as dirs and files as files
for root, dirs, files in os.walk("."):
path = root.split(os.sep)
print((len(path) - 1) * '---', os.path.basename(root))
for file in files:
print(len(path) * '---', file)
...
How to check if a symlink exists
...
-L returns true if the "file" exists and is a symbolic link (the linked file may or may not exist). You want -f (returns true if file exists and is a regular file) or maybe just -e (returns true if file exists regardless of type).
According to the ...
Windows batch file file download from a URL
I am trying to download a file from a website (ex. http://www.example.com/package.zip ) using a Windows batch file. I am getting an error code when I write the function below:
...