How to list all the tables in a particular database?
• What are cursors? Explain different types of cursors. What are the disadvantages of cursors? How can you avoid cursors? Cursors allow row-by-row processing of the result sets. Types of cursors: Static, Dynamic, Forward-only, Keyset-driven. Disadvantages of cursors: Each time you fetch a row from the cursor, it results in a network roundtrip. Cursors are also costly because they require more resources and temporary storage (results in more IO operations). Further, there are restrictions on the SELECT statements that can be used with some types of cursors. How to avoid cursor: • Most of the times, set based operations can be used instead of cursors. Here is an example: If you have to give a flat hike to your employees using the following criteria: Salary between 30000 and 40000 — 5000 hike Salary between 40000 and 55000 — 7000 hike Salary between 55000 and 65000 — 9000 hike In this situation many developers tend to use a cursor, determine each employee’s salary and update his salary
