Tutorial by Examples: me

Selective imports may also be renamed. void main() { import std.stdio : fooln = writeln; fooln("Hello world"); }

Converting a time to a string is a pretty common thing to do in Ruby. strftime is the method one would use to convert time to a string. Here are some examples: Time.now.strftime("%Y-%m-d %H:%M:S") #=> "2016-07-27 08:45:42" This can be simplified even further Time.now.str...

A simple cursor syntax, operating on a few example test rows: /* Prepare test data */ DECLARE @test_table TABLE ( Id INT, Val VARCHAR(100) ); INSERT INTO @test_table(Id, Val) VALUES (1, 'Foo'), (2, 'Bar'), (3, 'Baz'); /* Test data prepared */ /* Iterator variabl...

In some situations, one might want to return from a function before finishing an entire loop. The return statement can be used for this. function primefactor(n) for i in 2:n if n % i == 0 return i end end @assert false # unreachable end Usage: jul...

In Julia, a for loop can contain a comma (,) to specify iterating over multiple dimensions. This acts similarly to nesting a loop within another, but can be more compact. For instance, the below function generates elements of the Cartesian product of two iterables: function cartesian(xs, ys) f...

name = readline() if startswith(name, "A") println("Your name begins with A.") else println("Your name does not begin with A.") end Any expression, such as the if...else expression, can be put in statement position. This ignores its value but still execu...

Like any other expression, the return value of an if...else expression can be ignored (and hence discarded). This is generally only useful when the body of the expression has side effects, such as writing to a file, mutating variables, or printing to the screen. Furthermore, the else branch of an i...

d = Dates.dayofweek(now()) if d == 7 println("It is Sunday!") elseif d == 6 println("It is Saturday!") elseif d == 5 println("Almost the weekend!") else println("Not the weekend yet...") end Any number of elseif branches may be used...

A simplest Oozie application is consists of a workflow logic file (workflow.xml), workflow properties file (job.properties/job.xml) and required JAR files, scripts and configuration files. Except the workflow properties file, all the other files should to be stored in a HDFS location. The workflow p...

Merge two partitions into single one ALTER TABLE table_name MERGE PARTITIONS first_partition, second_partition INTO PARTITION splitted_partition TABLESPACE new_tablespace

Overview Create a queue that we can send a message to. Oracle will notify our stored procedure that a message has been enqueued and should be worked. We'll also add some subprograms we can use in an emergency to stop messages from being deqeued, allow dequeuing again, and run a simple batch job t...

Methods are defined with the def keyword, followed by the method name and an optional list of parameter names in parentheses. The Ruby code between def and end represents the body of the method. def hello(name) "Hello, #{name}" end A method invocation specifies the method name, the...

empty statement var statement expression statement do-while statement continue statement break statement return statement throw statement Examples: When the end of the input stream of tokens is encountered and the parser is unable to parse the input token stream as a single complete Pro...

Polymorphism is one of the pillar of OOP. Poly derives from a Greek term which means 'multiple forms'. Below is an example which exhibits Polymorphism. The class Vehicle takes multiple forms as a base class. The Derived classes Ducati and Lamborghini inherits from Vehicle and overrides the base cl...

CREATE TABLE ( id INT UNSIGNED NOT NULL AUTO_INCREMENT, ... PRIMARY KEY(id), ... ); Main notes: Starts with 1 and increments by 1 automatically when you fail to specify it on INSERT, or specify it as NULL. The ids are always distinct from each other, but... Do not make a...

The following examples use the UTF-8 encoding to represent filenames (and directory names) on disk. If you want to use another encoding, you should use Encode::encode(...). use v5.14; # Make Perl recognize UTF-8 encoded characters in literal strings. # For this to work: Make sure your text-editor...

Perl does not attempt to decode filenames returned by builtin functions or modules. Such strings representing filenames should always be decoded explicitly, in order for Perl to recognize them as Unicode. use v5.14; use Encode qw(decode_utf8); # Ensure that possible error messages printed to sc...

//Get instance of cache using System.Runtime.Caching; var cache = MemoryCache.Default; //Check if cache contains an item with cache.Contains("CacheKey"); //get item from cache var item = cache.Get("CacheKey"); //get item from cache or add item if not existing obje...

Even experienced Java developers tend to think that Java has only three protection modifiers. The language actually has four! The package private (a.k.a. default) level of visibility is often forgotten. You should pay attention to what methods you make public. The public methods in an application a...

Java manages memory automatically. You are not required to free memory manually. An object's memory on the heap may be freed by a garbage collector when the object is no longer reachable by a live thread. However, you can prevent memory from being freed, by allowing objects to be reachable that are...