2.sqlplus /nolog or sqlplus system/manager or. /sqlplus system/manager@ora9i。
3. SQL> connects as sysdba/(as sysoper) or connects as SYSDBA to internal/Oracle(Scott/Tiger) and connects as SYSDBA to Connsys/change _ on _ install.
4. SQL> starts; Start the database instance
5. View all current databases: select * from v$database.
Extended data:
ORACLE database system is a set of software products with distributed database as the core provided by ORACLE Company (Oracle Bone Inscriptions Company) in the United States, and it is one of the most popular client/server or B/S architecture databases at present.
Oracle database logical structure
It consists of at least one tablespace and database schema objects. Here, a schema is a collection of objects, and a schema object is a logical structure that directly references database data.
Schema objects include tables, views, sequences, stored procedures, synonyms, indexes, clusters and database chains. Logical storage structure includes table spaces, segments and ranges, which are used to describe how to use the physical space of the database.
file structure
The physical storage structure of the database consists of various physical files, mainly including data files, control files, redo log files, archive log files, parameter files, password files, warning files, etc.
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