Oracle Database 11g Release 2. Please also tag oracle for search purposes.
Oracle is a relational DBMS (Database Management System) created by Oracle Corporation. It supports a large number of languages and application development frameworks. Its primary languages are SQL, PL/SQL and Java.
11.2 was released for Linux on September 1st, 2009. New features added include RAC One Node, Improved data compression ratios (up to 20x), Edition Based Redefinition, Recursive Subquery Factoring, Instance Caging, Automatic Degree of Parallelism, Deferred Segment Creation, and the analytic function
Oracle makes a plethora of documentation available at https://docs.oracle.com/database/.
Questions about SQL should be tagged sql. If the question applies to an Oracle database it should probably also be tagged oracle.
Questions about PL/SQL should be tagged plsql as well as oracle.
Questions specific to a particular database version may be tagged with a version tag such as oracle11g-r2, oracle-11g, oracle-10g or oracle-9i, but they should also be tagged oracle.
Questions applicable to 18.104.22.168 through 22.214.171.124 should be tagged both oracle-11g and oracle.
Questions applicable to 126.96.36.199 through 188.8.131.52 should be tagged both oracle-11g-r2 and oracle.
Questions applicable to other versions should be tagged as oracle-10g, oracle-9i or oracle-8i as well as oracle.