How to restrict access to a sql server database from Azure?

Definition of sql server, database engine, dbms and how they all work?

• At work(I'm new) I have to use sql server 2008 R2 and from there connect to a server. Databases can be seen once opened. I use a client program(company program)which asks you to enter a database and a sql server name and am a bit puzzled.I assume databases are stored on the sql servers(database engine) From reading various articles this is what I wrote to make sense of the system- SQL server 2008 r2 is a database management system(dbms) that manages databases and allows users to access and manipulate data of a database. Using this database manager you can connect to a server. There are different server types. There is a type called database engine which is an underlying program that the database management system uses to create, read, delete data from a table. This SQL server can store multiple objects such as databases within the database management system. So... the dbms is just a program that allows that all to happen... Is this correct? Please correct me or add more detail. Thanks :)

• Answer:

  Absolutely. The above statement is correct. Your client application that connects to a given database server. The database server usually can contain any number of databases (exceptions do apply). There are also different database engines - SQL server series, MySql, postresql among many others (including Microsoft Access which isn't technically a true server database management system [DBMS]). As stated above they can operate different depending on the DBMS or it's settings. Most are CRUD (sorry but they are), this means they are "Create, Read, Update and Delete". So (in the case of SQL Server) a SQL script using one of the keywords INSERT, SELECT, UPDATE and DELETE will perform these CRUD transactions. There are other keywords that form the language syntax in SQL Server. These base 4 are part of SQL in general known as "Structured Query Language" but this has been extended somewhat to become DDL "Dynamic Data Language??" to perform other operations within the DBMS. In modern DBMS most systems are either Relational Database Management Systems (rDBMS) but you should also be aware there is also Object Relational (orDBMS) as well along with other types. In terms of SQL Server, it is much more than a DBMS, it is also a storage engine for scripts and custom functions. SQL Server has got very powerful that large sets of data can occupy multiple servers at the same time - clustering. There is "generally" a golden rule that a given DBMS "should" abide to. That is the ACID test, (atomicity, consistency, isolation, durability). I could right you an essay on it but I don't think you'll care too much, so if you want you can read all the sources of information below: