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The Basics The simplist way to convert one date format into another is to use strtotime() with date(). strtotime() will convert the date into a Unix Timestamp. That Unix Timestamp can then be passed to date() to convert it to the new format. $timestamp = strtotime('2008-07-01T22:35:17.02'); $new_...

Given some JSON file "foo.json" like: {"foo": {"bar": {"baz": 1}}} we can call the module directly from the command line (passing the filename as an argument) to pretty-print it: $ python -m json.tool foo.json { "foo": { "bar...

4.0 To uppercase $ v="hello" # Just the first character $ printf '%s\n' "${v^}" Hello # All characters $ printf '%s\n' "${v^^}" HELLO # Alternative $ v="hello world" $ declare -u string="$v" $ echo "$string" HELLO WORLD To l...

The Edges The browser creates a rectangle for each element in the HTML document. The Box Model describes how the padding, border, and margin are added to the content to create this rectangle. Diagram from CSS2.2 Working Draft The perimeter of each of the four areas is called an edge. Each edge ...

The @property decorator can be used to define methods in a class which act like attributes. One example where this can be useful is when exposing information which may require an initial (expensive) lookup and simple retrieval thereafter. Given some module foobar.py: class Foo(object): def __...

If you want to use @property to implement custom behavior for setting and getting, use this pattern: class Cash(object): def __init__(self, value): self.value = value @property def formatted(self): return '${:.2f}'.format(self.value) @formatted.setter def ...

SELECT your_columns, COUNT(*) OVER() as Ttl_Rows FROM your_data_set idnameTtl_Rows1example52foo53bar54baz55quux5 Instead of using two queries to get a count then the line, you can use an aggregate as a window function and use the full result set as the window. This can be used as a base for fur...

Let's say I have this data: Table items idnametag1exampleunique_tag2foosimple42barsimple3bazhello51quuxworld I'd like to get all those lines and know if a tag is used by other lines SELECT id, name, tag, COUNT(*) OVER (PARTITION BY tag) > 1 AS flag FROM items The result will be: idnametag...

If you want to get the versioned project's data, but you don't need any of the version control capabilities offered by Subversion, you could run svn export <URL> command. Here is an example: $ svn export https://svn.example.com/svn/MyRepo/MyProject/trunk As a result, you will get the proje...

git cherry-pick <commit-hash> will apply the changes made in an existing commit to another branch, while recording a new commit. Essentially, you can copy commits from branch to branch. Given the following tree (Source) dd2e86 - 946992 - 9143a9 - a6fd86 - 5a6057 [master] \ ...

To publish the changes you made in your working copy, run the svn commit command. IMPORTANT: Review your changes before committing them! Use svn status and svn diff to review the changes. Also, make sure you are in the correct path before performing a commit. If you updated many files across vari...

The X-macro approach can be generalized a bit by making the name of the "X" macro an argument of the master macro. This has the advantages of helping to avoid macro name collisions and of allowing use of a general-purpose macro as the "X" macro. As always with X macros, the mas...

docker run docker/whalesay cowsay 'Hello, StackExchange!' This command tells Docker to create a container from the docker/whalesay image and run the command cowsay 'Hello, StackExchange!' in it. It should print a picture of a whale saying Hello, StackExchange! to your terminal. If the entrypoin...

INSERT INTO Customers (FName, LName, PhoneNumber) SELECT FName, LName, PhoneNumber FROM Employees This example will insert all Employees into the Customers table. Since the two tables have different fields and you don't want to move all the fields over, you need to set which fields to insert int...

docker run -p "8080:8080" myApp docker run -p "192.168.1.12:80:80" nginx docker run -P myApp In order to use ports on the host have been exposed in an image (via the EXPOSE Dockerfile directive, or --expose command line option for docker run), those ports need to be bound to...

This uses the Dropbox .NET SDK to download a file from the Dropbox API at the remote path to the local file "Test", while tracking progress: var response = await client.Files.DownloadAsync(path); ulong fileSize = response.Response.Size; const int bufferSize = 1024 * 1024; var buffer ...

This query will return the number of tables in the specified database. USE YourDatabaseName SELECT COUNT(*) from INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE = 'BASE TABLE' Following is another way this can be done for all user tables with SQL Server 2008+. The reference is here. SELECT COUNT(...

std::this_thread is a namespace which has functions to do interesting things on the current thread from function it is called from. FunctionDescriptionget_idReturns the id of the threadsleep_forSleeps for a specified amount of timesleep_untilSleeps until a specific timeyieldReschedule running threa...

To get info from the requesting url (notice that req is the request object in the handler function of routes). Consider this route definition /settings/:user_id and this particular example /settings/32135?field=name // get the full path req.originalUrl // => /settings/32135?field=name // get...

Many IDEs provide support for generating HTML from Javadocs automatically; some build tools (Maven and Gradle, for example) also have plugins that can handle the HTML creation. However, these tools are not required to generate the Javadoc HTML; this can be done using the command line javadoc tool. ...