Large Lump On My Dog's Tail

What are the data warehouse and what differentiates them from OLTP systems

As mentioned above, a Data Warehouse is a computer file containing the data of an organization.
What is it?
-The aim is to 'focus' all the company's data in one place.
-It also integrates information from different sources.
-The data are inside processed / cleaned.
-The design is optimized in reading.
For all these reasons, therefore, we can consider it as a db-Ready Only.
What are the objectives?
-Ability to access all of the data, in one centralized database.
-Consistency and data consolidation.
-speed access to information by users.
-base for OLAP.

The data warehouse is a system OLAP (On Line Analytical Processing), analyzes the decision-making processes focusing on the component size information, is a subject oriented, integrated, historic and permanent. Being a sistema OLAP differisce dai sistemi OLTP (On Line Transaction Processing) che vengono utilizzati per analisi. I data warehouse non vengono mai cambiati come, invece, viene fatto con i sistemi OLTP.
Ancora, il sistema OLAP designa un insieme di tecniche software per l'analisi interattiva e veloce di grandi quantità di dati, che è possibile esaminare in modalità piuttosto complesse. Questa è la componente tecnologica base del data warehouse e, ad esempio, serve alle aziende per analizzare i risultati delle vendite, l'andamento dei costi di acquisto merci, al marketing per misurare il successo di una campagna pubblicitaria, ad una università i dati di un sondaggio ed altri casi simili. Mentre gli strumenti OLAP have the goal of performance and achievement in the search query on a scale as large as possible, as OLTP, however, are aimed at ensuring integrity and security of transactions.
A source of data for a data warehouse is an operating system. The micro data are summarized in two distinct levels: the first level (first level data mart) specifies the unit of time and in the second (second level of data marts) are stored permanently only data with higher frequency. The main approaches to develop a data warehouse are two: create a central data warehouse or data mart to create independent.