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Right and left outer joins are functionally equivalent. Neither provides any functionality that the other does not, so right and left outer joins may replace each other as long as the table order is switched. A Venn diagram representing the full join SQL statement between tables A and B.
A right join is employed over the Target (the INTO table) and the Source (the USING table / view / sub-query)--where Target is the left table and Source is the right one. The four possible combinations yield these rules:
For example, think of A as Authors, and B as Books. An Author can write several Books, and a Book can be written by several Authors. In a relational database management system, such relationships are usually implemented by means of an associative table (also known as join table, junction table or cross-reference table), say, AB with two one-to-many relationships A → AB and B → AB.
The right outer join ( ) behaves almost identically to the left outer join, but the roles of the tables are switched. The right outer join of relations R and S is written as R S . [ e ] The result of the right outer join is the set of all combinations of tuples in R and S that are equal on their common attribute names, in addition to tuples in ...
MongoDB can be used as a file system, called GridFS, with load-balancing and data-replication features over multiple machines for storing files. This function, called a grid file system, [36] is included with MongoDB drivers. MongoDB exposes functions for file manipulation and content to developers.
MongoDB, Inc. is an American software company that develops and provides commercial support for the source-available database engine MongoDB, a NoSQL database that stores data in JSON-like documents with flexible schemas.
Left bracket delimiter. Batch file: starting a parenthetical block can allow line continuation [6] Ruby: left parenthesis, left square bracket, or left curly bracket; Operator symbol. Ruby: as last object of line; comment may follow operator
Mongoose is a JavaScript object-oriented programming library that creates a connection between MongoDB and the Node.js JavaScript runtime environment. [ 1 ] [ 2 ] It provides a straightforward, schema-based solution to model application data.