Data Consistency

Data Consistency In Oracle Database, each user must see a consistent view of the data, including visible changes made by a user’s own transactions and committed transactions of other users. For example, the database must prevent the dirty read problem, which occurs when one transaction sees uncommitted changes made by another concurrent transaction. Oracle Database … Read more

Categories SQL

Introduction to Oracle SQL

Structured Query Language (SQL) is the set of statements with which all programs and usersaccess data in an Oracle Database. Application programs and Oracle tools often allow usersaccess to the database without using SQL directly, but these applications in turn must useSQL when executing the user’s request. SQL is a set-based declarative language that provides … Read more

Categories SQL

Sample Schemas

In Oracle Database, a database schema is a collection of logical data structures, or schema objects. A database user owns a database schema, which has the same name as the user name. Schema objects are user-created structures that directly refer to the data in the database. The database supports many types of schema objects, the … Read more

Categories SQL

Datafiles in Oracle (Physical Storage)

Overview of Data Files At the operating system level, Oracle Database stores database data in structures called data files. Every Oracle database must have at least one data file. Use of Data Files Oracle Database physically stores tablespace data in data files. Each nonpartitioned schema object and each partition of an object is stored in … Read more

Oracle Database 19c – Practical & Assignments

PARAMETER & PASSWORDFILE: * Create pfile from spfile to location ‘/home/oracle/init<sid.ora>’ * Create password file with sys password as oracle1 * Create parameterfile in different location /u01 & start the DB to up and running condition. * How to check all parameters associated with database? * How to change specific parameters with Scope=both/spfile/memory? * How … Read more