Foreign key

A Foreign Key is a field in a relational table that matches a candidate key of another table. The foreign key can be used to cross-reference tables.

For example, say we have two tables, a CUSTOMER table that includes all customer data, and an ORDER table that includes all customer orders. The intention here is that all orders must be associated with a customer that is already in the CUSTOMER table. To do this, we will place a foreign key in the ORDER table and have it relate to the primary key of the CUSTOMER table.

Foreign key – Wikipedia, the free encyclopedia.

Quantum Processor Hooks Up with Quantum Memory

Although quantum computing is now mostly a research subject, it holds out the promise of computers far more capable than those we use today. The power of quantum computers comes from their version of the most basic unit of computing, the bit. In a conventional computer, a bit can represent either 1 or 0 at any time. Thanks to the quirks of quantum mechanics, the equivalent in a quantum computer, a qubit, can represent both values at once. When qubits in such a “superposition” state work together, they can operate on exponentially more data than the same number of regular bits. As a result, quantum computers should be able to defeat encryption that is unbreakable in practice today and perform highly complex simulations.

via Quantum Processor Hooks Up with Quantum Memory – Technology Review.

Reading this makes my head want to explode.

Scientists Claim New Map of Spiralling Light to Boost Fibre Optic Broadband Speed

Scientists working at the Institute of Ultrafast Spectroscopy and Lasers (IUSL), which is part of the City College of New York (CUNY), have discovered a new way of mapping spiralling light that could allow telecommunications operators the ability to harness “untapped data channels” within fibre optic broadband ISP cables.

Scientists Claim New Map of Spiralling Light to Boost Fibre Optic Broadband Speed − ISPreview UK News.