Search Interview Questions |  More than 3000 questions in repository. There are more than 900 unanswered questions. Click here and help us by providing the answer. Have a video suggestion. Click Correct / Improve and please let us know. |
|
|||
| |||||||||||||||||||||||||||
| Database - Interview Questions and Answers for 'Infosys' - 4 question(s) found - Order By Newest | |||||||||||||||||||||||||||
 Frequently asked in Cognizant ( Based on 2 feedback ) | |||||||||||||||||||||||||||
| |||||||||||||||||||||||||||
| Ans. Inner join is the intersection of two tables on the condition defined by the where clause i.e will get records from both tables matched by a column. Outer join is the union of two tables i.e will get all records from both tables and will put null in the columns where related records are not present. Left Outer join is the left union of two tables i.e all records from the table on the left and values from the right table for related records else null for the columns from right table. Right Outer join is the right union of two tables i.e all records from the table on the right and values from the left table for related records else null for the columns from left table. | |||||||||||||||||||||||||||
| Help us improve. Please let us know the company, where you were asked this question : | |||||||||||||||||||||||||||
 Discuss Correct / Improve  sql inner join outer join right join left join  Asked in 24 Companies  basic  frequent | |||||||||||||||||||||||||||
| |||||||||||||||||||||||||||
| Ans. The external tables feature is a complement to existing SQL Loader functionality. It enables to access data in external sources as if it were in a table in the database. We have used it few times for replicating tables across different database systems. | |||||||||||||||||||||||||||
| Help us improve. Please let us know the company, where you were asked this question : | |||||||||||||||||||||||||||
| Discuss Correct / Improve external table oracle Asked in 1 Companies rare | |||||||||||||||||||||||||||
| |||||||||||||||||||||||||||
| Ans. A dirty read occurs when a transaction is allowed to read data from a row that has been modified by another running transaction but not yet committed. | |||||||||||||||||||||||||||
| Help us improve. Please let us know the company, where you were asked this question : | |||||||||||||||||||||||||||
| Discuss Correct / Improve database transaction Asked in 8 Companies | |||||||||||||||||||||||||||
| |||||||||||||||||||||||||||
| Ans. ORM is the mapping technique, which maps object with relational data model. As we know that in java we need objects we can not user data in relational(in table form). So ORM is set of guideline which allows us to map relational data model in object form. | |||||||||||||||||||||||||||
| Help us improve. Please let us know the company, where you were asked this question : | |||||||||||||||||||||||||||
| Discuss Correct / Improve orm Asked in 1 Companies frequent | |||||||||||||||||||||||||||
