DataBase Administrator (DBA) Interview Questions and Answers
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8. Do View contain Data?
Views do not contain or store data.
9. What are the Referential actions supported by FOREIGN KEY integrity constraint?
UPDATE and DELETE Restrict - A referential integrity rule that disallows the update or deletion of referenced data. DELETE Cascade - When a referenced row is deleted all associated dependent rows are deleted.
10. What are the type of Synonyms?
There are two types of Synonyms Private and Public
11. Where would you look for errors from the database engine?
In the alert log.
12. Compare and contrast TRUNCATE and DELETE for a table.
Both the truncate and delete command have the desired outcome of getting rid of all the rows in a table. The difference between the two is that the truncate command is a DDL operation and just moves the high water mark and produces a now rollback. The delete command, on the other hand, is a DML operation, which will produce a rollback and thus take longer to complete.
13. Give the reasoning behind using an index.
Faster access to data blocks in a table.
14. 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.
15. What type of index should you use on a fact table?
A Bitmap index.
(Continued on next part...)