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Find f(n): nth Fibonacci number. The problem is quite easy when n is relatively small. We can use simple recursion, f(n) = f(n-1) + f(n-2), or we can use dynamic programming approach to avoid the calculation of same function over and over again. But what will you do if the problem says, Given 0 <...

Consider the following Java classes: class Foo { private Bar bar; public void foo() { bar.baz(); } } As can be seen, the class Foo needs to call the method baz on an instance of another class Bar for its method foo to work successfully. Bar is said to be a dependency for Foo sin...

The same examples as shown above with XML configuration can be re-written with Java configuration as follows. Constructor injection @Configuration class AppConfig { @Bean public Bar bar() { return new Bar(); } @Bean public Foo foo() { return new Foo(bar()); } } Property in...

Dependencies can be autowired when using the component scan feature of the Spring framework. For autowiring to work, the following XML configuration must be made: <context:annotation-config/> <context:component-scan base-package="[base package]"/> where, base-package is th...

Constructor injection through Java configuration can also utilize autowiring, such as: @Configuration class AppConfig { @Bean public Bar bar() { return new Bar(); } @Bean public Foo foo(Bar bar) { return new Foo(bar); } }

One easy algorithm to implement as a recursive function is factorial. ;;Compute the factorial for any n >= 0. Precondition: n >= 0, n is an integer. (defun factorial (n) (cond ((= n 0) 1) ;; Special case, 0! = 1 ((= n 1) 1) ;; Base case, 1! = 1 (t ...

DBCC commands enable user to maintain space in database, clean caches, shrink databases and tables. Examples are: DBCC DROPCLEANBUFFERS Removes all clean buffers from the buffer pool, and columnstore objects from the columnstore object pool. DBCC FREEPROCCACHE -- or DBCC FREEPROCCACHE (0x06...

DBCC commands enable user to validate state of database. ALTER TABLE Table1 WITH NOCHECK ADD CONSTRAINT chkTab1 CHECK (Col1 > 100); GO DBCC CHECKCONSTRAINTS(Table1); --OR DBCC CHECKCONSTRAINTS ('Table1.chkTable1'); Check constraint is added with nocheck options, so it will not be ...

DBCC commands can show information about database objects. DBCC PROCCACHE Displays information in a table format about the procedure cache. DBCC OUTPUTBUFFER ( session_id [ , request_id ]) Returns the current output buffer in hexadecimal and ASCII format for the specified session_id (and o...

DBCC statements act as Database Console Commands for SQL Server. To get the syntax information for the specified DBCC command use DBCC HELP (...) statement. The following example returns all DBCC statements for which Help is available: DBCC HELP ('?'); The following example returns options f...

Git config allows you to customize how git works. It is commonly used to set your name and email or favorite editor or how merges should be done. To see the current configuration. $ git config --list ... core.editor=vim credential.helper=osxkeychain ... To edit the config: $ git config &lt...

If you find managing QThreads and low-level primitives like mutexes or semaphores too complex, Qt Concurrent namespace is what you are looking for. It includes classes which allow more high-level thread management. Let's look at Concurrent Run. QtConcurrent::run() allows to run function in a new th...

For Umbraco 7 the requirements are IIS 7 or higher Database, one of the following: SQL CE, SQL Server 2008 or higher or MySQL with support for case insensitive queries) ASP.NET 4.5 or 4.5.1. Full-Trust Ability to set file/folder permissions for the user that "owns" the Application P...

If you want to do different things based on the kind of error, use multiple rescue clauses, each with a different error type as an argument. def divide(x, y) begin return x/y rescue ZeroDivisionError puts "Don't divide by zero!" return nil rescue TypeError put...

select sysdate from dual

select :start_value + level -1 n from dual connect by level <= :end_value - :start_value + 1

You can read content of file using OPENROWSET(BULK) function and store content in some table: INSERT INTO myTable(content) SELECT BulkColumn FROM OPENROWSET(BULK N'C:\Text1.txt', SINGLE_BLOB) AS Document; SINGLE_BLOB option will read entire content from a file as single cell. ...

Yu can define format of the file that will be imported using FORMATFILE option: INSERT INTO mytable SELECT a.* FROM OPENROWSET(BULK 'c:\test\values.txt', FORMATFILE = 'c:\test\values.fmt') AS a; The format file, format_file.fmt, describes the columns in values.txt: 9.0 2 1 SQ...

You can use OPENROWSET to read content of file and pass it to some other function that will parse results. The following example shows hot to read entire content of JSON file using OPENROWSET(BULK) and then provide BulkColumn to OPENJSON function that will parse JSON and return columns: SELECT boo...

There are three ways to quote something using a Julia function: julia> QuoteNode(:x) :(:x) julia> Meta.quot(:x) :(:x) julia> Expr(:quote, :x) :(:x) What does "quoting" mean, and what is it good for? Quoting allows us to protect expressions from being interpreted as sp...