What is schema ?
A schema is collection of database objects of a user. Read more »
‘Oracle Interview Questions’ - KyaPoocha.com
Explain the relationship among database, tablespace and data file ?
Each databases logically divided into one or more tablespaces one or more data files are explicitly created for each tablespace. Read more »
What is SYSTEM tablespace and when is it created ?
Every Oracle database contains a tablespace named SYSTEM, which is automatically created when the database is created. The SYSTEM tablespace always contains the... Read more »
What are the components of logical database structure of Oracle database
There are tablespaces and database’s schema objects. Read more »
What are the components of physical database structure of Oracle database ?
Oracle database is comprised of three types of files. One or more datafiles, two are more redo log files, and one or more control files. Read more »
Give the two types of tables involved in producing a star schema and the type of data they hold.
Fact tables and dimension tables. A fact table contains measurements while dimension tables will contain data that will help describe the fact tables. Read more »
How does one change the default Oracle passwords?
Passwords for SYS/CHANGE_ON_INSTALL, SYSTEM/MANAGER, and SAPR3/SAP should be changed for security reasons. The easiest way to change them is using the R3INST program.... Read more »
Is it better to put code in triggers or procedures? What is the difference?
In earlier releases of Oracle it was better to put as much code as possible in procedures rather than triggers. At that stage procedures executed faster than triggers... Read more »
What is a mutating and constraining table?
“Mutating” means “changing”. A mutating table is a table that is currently being modified by an update, delete, or insert statement. When... Read more »
What are the difference between DDL, DML and DCL commands?
DDL (Data Definition Language) statements are used to define the database structure or schema. Some examples: 1. CREATE - to create objects in the database 2. ALTER... Read more »
What’s the command to change the SQL prompt name?
SQL> set sqlprompt “database-1 > ” database-1 > database-1 > Read more »
What’s the command to see the current user name?
Sql> show user; Read more »
Explain the difference between $ORACLE_HOME and $ORACLE_BASE.
ORACLE_BASE is the root directory for oracle. ORACLE_HOME located beneath ORACLE_BASE is where the oracle products reside. Read more »
Explain an ORA-01555.
You get this error when you get a snapshot too old within rollback. It can usually be solved by increasing the undo retention or increasing the size of rollbacks.... Read more »
How would you go about increasing the buffer cache hit ratio?
Use the buffer cache advisory over a given workload and then query the v$db_cache_advice table. If a change was necessary then I would use the alter system set db_cache_size... Read more »