How do SQL queries will effect the performance of the application?
Yes, sql queries make a lot of impact on the whole performance of application. A poorly written sql query by a developer can take long time to generate a report or retrieve data from data base. So, we need to take few precautions while writing queries, as a database tester I will also review the queries written by a developer. For example: get rid of nested sql queries as much as possible and make use of joins.