Yes MYSQL is free to everyone and it comes under open source project...
Mysql::
1).is a multithreaded, multi-user SQL database management system (DBMS).
2).The basic program runs as a server providing multiuser access to a number of databases.
3).Libraries for accessing MySQL databases are available in all major programming languages with language-specific APIs. In addition, an ODBC interface called MyODBC allows additional programming languages that support the ODBC interface to communicate with a MySQL database, such as ASP or ColdFusion. The MySQL server and official libraries are mostly implemented in ANSI C/ANSI C++.
4).MySQL is popular for web applications and acts as the database component of the LAMP, MAMP, and WAMP platforms(Linux/Mac/Windows-Apache-MySQL-PHP/Perl/Python), and for open-source bug tracking tools like Bugzilla. Its popularity for use with web application is closely tied to the popularity of PHP, which is often combined with MySQL.
5) cross platform
SQL
1)commonly expanded as Structured Query Language, is a computer language designed for the retrieval and management of data in relational database management systems, database schema creation and modification, and database object access control management.
2)SQL is a set-based, declarative query language, not an imperative language such as C or BASIC. However, there are extensions to Standard SQL which add procedural programming language functionality, such as control-of-flow constructs.
3) hardly supports client server architecture....well it is mother of all advanced RDBMS(oracle,mysql,db2)
4).Common criticisms of SQL include a perceived lack of cross-platform portability between vendors, inappropriate handling of missing data (see Null (SQL)), a complex three-valued logic system, and its complex and occasionally ambiguous language grammar and semantics.
hope this helps
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