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Input table data (People table) IdNameAge1John232Jane31 Query SELECT Id, Name, Age FROM People FOR JSON PATH Result [ {"Id":1,"Name":"John","Age":23}, {"Id":2,"Name":"Jane","Age":31} ]

JSON_VALUE and JSON_QUERY functions parse JSON text and return scalar values or objects/arrays on the path in JSON text. DECLARE @json NVARCHAR(100) = '{"id": 1, "user":{"name":"John"}, "skills":["C#","SQL"]}' SELECT JS...

The Windows API is provided by means of a C-callable interface. Success or failure of an API call is reported strictly through return values. Exceptions aren't part of the documented contract (although some API implementations can raise SEH exceptions, e.g. when passing a read-only lpCommandLine arg...

Some API calls return a single failure/success flag, without any additional information (e.g. GetObject): if ( GetObjectW( obj, 0, NULL ) == 0 ) { // Failure: no additional information available. }

In addition to a failure/success return value, some API calls also set the last error on failure (e.g. CreateWindow). The documentation usually contains the following standard wording for this case: If the function succeeds, the return value is <API-specific success value>. If the function...

Some API calls can succeed or fail in more than one way. The APIs commonly return additional information for both successful invocations as well as errors (e.g. CreateMutex). if ( CreateMutexW( NULL, TRUE, L"Global\\MyNamedMutex" ) == NULL ) { // Failure: get additional information. ...

When implementing SFINAE using std::enable_if, it is often useful to have access to helper templates that determines if a given type T matches a set of criteria. To help us with that, the standard already provides two types analog to true and false which are std::true_type and std::false_type. The...

In Drupal 7 and lower, your configuration is probably stored using the Features module. To update a feature with changes from the databases use this command: drush features-update [feature-name] // e.g. drush features-update content_type_news You can also use this shorthand: drush fu [feature-n...

Use unpacking to extract the first element and ensure it's the only one: a, = iterable def foo(): yield 1 a, = foo() # a = 1 nums = [1, 2, 3] a, = nums # ValueError: too many values to unpack

Start with iter() built-in to get iterator over iterable and use next() to get elements one by one until StopIteration is raised signifying the end: s = {1, 2} # or list or generator or even iterator i = iter(s) # get iterator a = next(i) # a = 1 b = next(i) # b = 2 c = next(i) # raises S...

You can write the default protocol implementation for a specific class. protocol MyProtocol { func doSomething() } extension MyProtocol where Self: UIViewController { func doSomething() { print("UIViewController default protocol implementation") } } class M...

Setting up settings.py from django.utils.translation import ugettext_lazy as _ USE_I18N = True # Enable Internationalization LANGUAGE_CODE = 'en' # Language in which original texts are written LANGUAGES = [ # Available languages ('en', _("English")), ('de', _("Germ...

In order to efficiently handle cycle detection, we consider each node as part of a tree. When adding an edge, we check if its two component nodes are part of distinct trees. Initially, each node makes up a one-node tree. algorithm kruskalMST'(G: a graph) sort G's edges by their value MST ...

The above forest methodology is actually a disjoint-set data structure, which involves three main operations: subalgo makeSet(v: a node): v.parent = v <- make a new tree rooted at v subalgo findSet(v: a node): if v.parent == v: return v return findSet(v.parent...

We can do two things to improve the simple and sub-optimal disjoint-set subalgorithms: Path compression heuristic: findSet does not need to ever handle a tree with height bigger than 2. If it ends up iterating such a tree, it can link the lower nodes directly to the root, optimizing future trav...

Sort the edges by value and add each one to the MST in sorted order, if it doesn't create a cycle. algorithm kruskalMST(G: a graph) sort G's edges by their value MST = an empty graph for each edge e in G: if adding e to MST does not create a cycle: add e to MST ...

You can calculate a number in the Fibonacci sequence using recursion. Following the math theory of F(n) = F(n-2) + F(n-1), for any i > 0, // Returns the i'th Fibonacci number public int fib(int i) { if(i <= 2) { // Base case of the recursive function. // i is either 1...

JSON stands for "JavaScript Object Notation", but it's not JavaScript. Think of it as just a data serialization format that happens to be directly usable as a JavaScript literal. However, it is not advisable to directly run (i.e. through eval()) JSON that is fetched from an external source...

HTML also provides the tables with the <thead>, <tbody>, <tfoot>, and <caption> elements. These additional elements are useful for adding semantic value to your tables and for providing a place for separate CSS styling. When printing out a table that doesn't fit onto one (pa...

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