Oracle interview Q&A

Posted by tib on May 16th, 2019

Oracle is one of the most important vendors within the enterprise IT market and therefore the shorthand name of its flagship product, a relational database management system (RDBMS) that is formally known as Oracle database. The information code sits at the middle of the many company IT environments, supporting a mixture of dealings process, business intelligence and analytics applications.

What is the usage of control file in Oracle?

In Oracle, management file is used for database recovery. The control file is also wont to identify the database and redo log files that must be opened for Best Oracle Training Institutes in Marathahalli database operation to go ahead, whenever an instance of an ORACLE database begins.

What is a synonym?

A synonym is also called alias for a table, view, sequence or program unit.

What are the different kinds of synonyms?

There are 2 kinds of synonyms or alias:

• Private: It will only accessed by the owner.
• Public: It will be accessed by any database user.

What is the usage of synonyms?

Synonym will be wont to hide the important name and owner of an object.

• It provides public access to an object.
• It additionally provides location transparency for tables, views or program units of a remote database.
• It simplifies the SQL statements for database users.

How do you store pictures in a database?

Yes, you'll store pictures during a info using Long data type. This data type is used to store binary knowledge for two gigabytes of length. However, the table will have only 1 Long data type.

What is BLOB data type in Oracle?

BLOB data type is a data type with variable length binary string. It’s wont to store 2 gigabytes memory. For BLOB data type, the length must be per bytes.

What the distinction between TRANSLATE and REPLACE in Oracle?

Translate is used to substitute a character by another character while Replace is used to substitute a single character with a word.

What are the different types of database objects?

A list of various types of database objects:

• Tables: this can be a set of elements organized in vertical and horizontal fashion.
• Table spaces: in Oracle table space is a logical storage unit.
• Views: its virtual table derived from one or additional tables.
• Indexes: this can be a performance standardization methodology to method the records.
• Synonyms: this can be a reputation for tables.

In Oracle database what is the usage of Save Points?

It is used to divide a transaction into smaller parts. It enables rolling back a part of a transaction. There are most five save points allowed in Oracle info. Whenever an error is encountered, it's possible to rollback from the point where the SAVEPOINT has been saved.

What is the distinction between post-database commit and post-form commit?

The post-form commit is fired during the post and commit transactions method, once the database commit happens. The post-database commit trigger is executed once Oracle Training in Marathahalli  Oracle forms issue the plan to finalized transaction .

What do you meaning by Redo Log file mirroring?

Mirroring may be a method of getting a duplicate of Redo log files. It’s done by making cluster of log files along. This ensures that LGWR automatically writes them to any or all the members of this on-line redo log cluster. If the cluster fails, the database automatically switches over to the next cluster. It diminishes the performance.

What is that means of recursive hints in Oracle?

The number of times a dictionary table is repeatedly known as by various processes is known as recursive hint. Recursive hint is occurred because of the little size of information dictionary cache.

What area unit the constraints of CHECK constraint?

The main limitation of CHECK constraint is that the condition should be a Boolean expression evaluated using the values within the row being inserted or updated and cannot contain sub queries.

What is the utilization of GRANT option in IMP command?

GRANT is used to import object grants.

What is the utilization of ROWS option in IMP command?

The ROWS option indicates whether the table rows should be imported or not in the particular table.

What is the utilization of INDEXES option in IMP command?

The INDEXES option is used to see whether indexes area unit foreign.

What is the utilization of IGNORE option in IMP command?

The IGNORE option indicates to specify how object creation errors should be handled.

What SHOW option indicates in IMP command? 

The SHOW option specifies once the value of show=y, the DDL within the export file is displayed.

What FILE param indicates in IMP command?

FILE param indicates to specify the name of the export file to import. Multiple files are often listed, separated by commas.

How many extensions used by Oracle reports?

Reports are use to make business modify with the ability to produce info of all level among or outside during a secure manner. Reports uses REP files and RDF file extensions.