Oracle
An Oracle database consists of a collection of data managed by an Oracle database management system. Popular generic usage also uses the term to refer to the Oracle DBMS management software, but not necessarily to a specific database under its control.
One can refer to the Oracle database management system unambiguously as Oracle DBMS or (since it manages databases which have relational characteristics) as Oracle RDBMS.
An Oracle database comprises an instance and data storage. The instance comprises a set of operating system processes and memory structures that interact with the storage. Typical processes include PMON (the process monitor) and SMON (the system monitor).
Oracle users refer to the server-side memory-structure as the SGA (System Global Area). The SGA typically holds cache information like data-buffers, SQL commands and user information. In addition to storage, the database consists of online redo logs (which hold transactional history). Processes can in turn archive the online redo logs into archive logs (offline redo logs), which provide the basis (if necessary) for data recovery and for some forms of data replication.
The Oracle RDBMS stores data logically in the form of tablespaces and physically in the form of data files. Tablespaces can contain various types of segments, for example, Data Segments, Index Segments etc. Segments in turn comprise one or more extents. Extents comprise groups of contiguous data blocks. Data blocks form the basic units of data storage. At the physical level, data files comprise one or more data blocks, where the blocksize can vary.
Oracle Corporation itself blurs the very useful distinction between:
1. data managed by an Oracle RDBMS
2. an Oracle database, and
3. the Oracle RDBMS software itself
when it refers nowadays to the Oracle RDBMS (the software it sells for the purpose of managing databases) as the Oracle Database. The distinction between the managed data (the database) and the software which manages the data (the DBMS / RDBMS) relies, in Oracle's marketing literature, on the capitalisation of the word database.
Oracle Corporation produces and markets the Oracle DBMS, which many database applications use extensively on many popular computing platforms.
FOR MORE INFORMATION ,DETAILS AND RESOURCES ON ORACLE
An Oracle database consists of a collection of data managed by an Oracle database management system. Popular generic usage also uses the term to refer to the Oracle DBMS management software, but not necessarily to a specific database under its control.
One can refer to the Oracle database management system unambiguously as Oracle DBMS or (since it manages databases which have relational characteristics) as Oracle RDBMS.
An Oracle database comprises an instance and data storage. The instance comprises a set of operating system processes and memory structures that interact with the storage. Typical processes include PMON (the process monitor) and SMON (the system monitor).
Oracle users refer to the server-side memory-structure as the SGA (System Global Area). The SGA typically holds cache information like data-buffers, SQL commands and user information. In addition to storage, the database consists of online redo logs (which hold transactional history). Processes can in turn archive the online redo logs into archive logs (offline redo logs), which provide the basis (if necessary) for data recovery and for some forms of data replication.
The Oracle RDBMS stores data logically in the form of tablespaces and physically in the form of data files. Tablespaces can contain various types of segments, for example, Data Segments, Index Segments etc. Segments in turn comprise one or more extents. Extents comprise groups of contiguous data blocks. Data blocks form the basic units of data storage. At the physical level, data files comprise one or more data blocks, where the blocksize can vary.
Oracle Corporation itself blurs the very useful distinction between:
1. data managed by an Oracle RDBMS
2. an Oracle database, and
3. the Oracle RDBMS software itself
when it refers nowadays to the Oracle RDBMS (the software it sells for the purpose of managing databases) as the Oracle Database. The distinction between the managed data (the database) and the software which manages the data (the DBMS / RDBMS) relies, in Oracle's marketing literature, on the capitalisation of the word database.
Oracle Corporation produces and markets the Oracle DBMS, which many database applications use extensively on many popular computing platforms.
FOR MORE INFORMATION ,DETAILS AND RESOURCES ON ORACLE