Technology is considered to be moving at a rapid pace. And this would be holding especially true in the field of computer science as well as telecommunications with new software and its applications which would be updated constantly. As an IT professional this would be meaning that you should always be on your toes. And companies in this industry would be always looking out for programmers who would be well versed in the latest developments. Regardless of your experience in the field expert or novice, you could be acing any interview you appear for. And to help you do that, here would be the 15 of the most frequently asked Oracle interview questions as well as their answers. Do check out the SPOTO Club’s study dumps, to help you out to ensure your success in Oracle Certification.
1. What would be the purpose of Oracle? And how it works?
Oracle, or Oracle Database, is believed to be a Relational DataBase Management System (RDBMS). It is considered to be the software that would be utilized for processing, storing, retrieving and manipulating data. It would be based on PQ/SQL as an extension over SQL (Structured Query Language). Oracle Certification would be working by making use of memory threads within the main memory system for analyzing, managing and retrieving data.
2. In what ways could you write comments in Oracle?
For single statements, you could use two dashes (--).
For a block statement you could use (*--*).
3. What would be Constraints and how could we use them?
Constraints would be the rules that you would be setting up for your data.
They could be utilized either during table creation or later, for altering the table.
4. Differentiate between Primary as well as Unique key?
A Primary key is utilized for identifying a particular record in the data database there could be only on Primary key for a table as well as it would be required not to holding a null value.
On the other hand, the Unique key would be utilized to avoid duplication of values in the system. There could be more than one Unique keys for a table and it would be allowed to holding a null value.
5. How is TRANSLATE dissimilar from REPLACE?
You could be utilizing to TRANSLATE when you wish to replace characters one after another, while REPLACE would be allowing you to replace an entire set of characters with a latest complete string.
6. How do AGGREGATE and COALESCE differ?
The AGGREGATE command would be helping you to join the values of multiple records into a single value. COALESCE command would be returning the value in the table setting to not null. For instance functions like sum, average, as well as count.
7. What would you know about set operations in Oracle?
They are commands which would be utilized for combining queries in order to receive unique results.
For instance, INTERSECT would be returning the results common to every query executed. MINUS would be allowing you to obtain a result distinctive only to the first query. UNION as well as UNION ALL combining all the results obtained from all the queries, only that UNION ALL would be keeping the duplicate record.
8. What do you understand by Joins?
Joins are commands that could be utilized for collecting data from several different tables having a common column. Besides having a firm grasp over your subject, make it a point for listening to the interviewer suspiciously. Sometimes even the easiest questions could seem hard if you wouldn’t understand it.
Here were some basic technical points of Oracle Certification, but there is more to it, and for that, you would require good and reliable training courses, such you would found at the SPOTO Club.