Tutorial by Examples: pt

probably the most common misconception about asnycio is that it lets you run any task in parallel - sidestepping the GIL (global interpreter lock) and therefore execute blocking jobs in parallel (on separate threads). it does not! asyncio (and libraries that are built to collaborate with asyncio) b...

Temp tables must have unique IDs (within the session, for local temp tables, or within the server, for global temp tables). Trying to create a table using a name that already exists will return the following error: There is already an object named '#tempTable' in the database. If your query pro...

$username = "[email protected]" $pwdTxt = Get-Content "C:\temp\Stored_Password.txt" $securePwd = $pwdTxt | ConvertTo-SecureString $credObject = New-Object System.Management.Automation.PSCredential -ArgumentList $username, $securePwd # Now, $credObject is having the credential...

COPY products TO 'D:\csv_backup\products_db.csv' DELIMITER ',' CSV HEADER; COPY categories TO 'D:\csv_backup\categories_db.csv' DELIMITER ',' CSV HEADER;

Eventloop in pseudo code An event loop is a loop that waits for events and then reacts to those events while true: wait for something to happen react to whatever happened Example of a single-threaded HTTP server with no event loop while true: socket = wait for the next TCP c...

JUnit can also be used to test if a method throws a specific exception for a given input. In this example we will test if the following method really throws an exception if the Boolean format (input) is not recognized/unknown: public static boolean parseBoolean(@NonNull String raw) throws IllegalA...

When dealing with large configuration sets of value, it might become quite unhandy to load them one buy one. Option model which comes with asp.net offers a convenient way to map a section to a dotnet poco: For instance, one might hydrate StorageOptions directly from a configuration section b addin...

From Apple documentation for IV, This parameter is ignored if ECB mode is used or if a stream cipher algorithm is selected. func AESEncryption(key: String) -> String? { let keyData: NSData! = (key as NSString).data(using: String.Encoding.utf8.rawValue) as NSData! ...

Depth First Traversal (or Search) for a graph is similar to Depth First Traversal of a tree. The only catch here is, unlike trees, graphs may contain cycles, so we may come to the same node again. To avoid processing a node more than once, we use a boolean visited array. Below algorithm presents th...

Bullet This one particularly blew my mind. The bullet gem helps you kill all the N+1 queries, as well as unnecessarily eager loaded relations. Once you install it and start visiting various routes in development, alert boxes with warnings indicating database queries that need to be optimized will p...

Backreferences "Backreferences" are references in a search regex to capture groups in the same search regex. The "search regex" is the regex used in the "Find" field of the Find/Replace dialog box. Here is the most common backreference syntax: Absolute: (group one)...

A regex in Notepad++ may have as many capture groups as desired. (one)(two)(three)...(nine)(more than nine groups!)... Anonymous capture groups use the standard syntax: (group) Named capture groups may use either of following syntax formats: (?<name>group) (?'name'group) Anonymo...

Get-ChildItem -Path $PSScriptRoot This example retrieves the list of child items (directories and files) from the folder where the script file resides. The $PSScriptRoot automatic variable is $null if used from outside a PowerShell code file. If used inside a PowerShell script, it automatically ...

Moshi has built-in support for reading and writing Java’s core data types: Primitives (int, float, char...) and their boxed counterparts (Integer, Float, Character...). Arrays Collections Lists Sets Maps Strings Enums It supports your model classes by writing them out field-by-field. In ...

StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder() .detectDiskWrites() .penaltyLog() //Logs a message to LogCat .build())

$ cut -d, -f1,3 <<<"a,,b,c,d,e" a,b is rather obvious, but with space-delimited strings it might be less obvious to some $ cut -d ' ' -f1,3 <<<"a b c d e" a b cut cannot be used to parse arguments as the shell and other programs do.

One to Many Lets say that each Post may have one or many comments and each comment belongs to just a single Post. so the comments table will be having post_id. In this case the relationships will be as follows. Post Model public function comments() { return $this->belongsTo(Post::class...

Concept AsyncTask is a class that allows running operations in the background, with the results being published on the UI thread. The main purpose is to eliminate all the boilerplate code for starting/running a thread by eliminating the handlers and all the stuff that are needed for manipulating t...

Steps: clone the gradle-script-kotlin project copy/paste from the cloned project to your project: build.gradle.kts gradlew gradlew.bat settings.gradle update the content of the build.gradle.kts based on your needs, you can use as inspiration the scripts in the project just clo...

As of Ruby 2.4.0, you can start an interactive IRB session inside any Ruby script using these lines: require 'irb' binding.irb This will start an IBR REPL where you will have the expected value for self and you will be able to access all local variables and instance variables that are in scope....