Question

1. Fortunately, once an application that accesses a database is tuned for optimal relational access to the data, there is never any performance degradation after that.

.True

.False

2 Monitoring a database system for performance management purposes means to watch the system as it runs, paying particular attention to statistics gathered by the RDBMS

. True

. False

3. RDBMS, in general, during normal operational use, use _______________ cache(s). Choose the best answer

a. exactly two

b. no

c. a number of

d. exactly one

4. Indexes can be used to avoid having the RDBMS sorted returned data.

. True

. False

Answer 1

1.TRUE

If an application that access certain data is tuned or upgraded to optimal relational access there are maximum chances of better performance as optimization by name says that data is retrieved fast and efficiently.

  Here in this case we are optimizing query so that we can access data fast.Query optimizer chooses best plan among all plans that take less amount of time and less cost for execution of query.So the performance will be increased.

2.TRUE

Monitoring a database management system means looking into the statistics developed by the monitoring tool.We have many tools for monitoring a database.The main objective of monitoring tool is to decrease downtime and increase performance.The best monitoring tool not only generate alert in case of any issue but also give the cause of why the issue is raised .Based on the cause we can trouble shoot the problem easily.The statistics include CPU utilization ,memory utilization,user sessions etc.

3.TWO

Caching is the technique to temporarily store recently queried data so that one can access it next time efficiently.Generally a database uses two types of cache internal cache and query cache.

In internal cache based on certain patterns the data is stored and we do not have any influence on it but in query cache if we make a query more than once then it is automatically returned by RAM.

But a database can use as many number of caches based on requirement.

4.FALSE

Indexing is mainly used to access the data in database quickly.Indices are used to increase performance of system by decreasing the number of disk accesses so that we can execute query fast.

Using indexing we may or may not get sorted data.As we create the indexes using few database columns in that one column may be search column having certain key to access the data quickly so by using indices we access data quickly.We can also get data in sorted order using indices by grouping columns in ascending or descending order.