How to use ORDER BY query in MySQL


  • used to sort the result-set by one or more columns
  • ORDER BY keyword sorts the records in ascending order by
  • To sort the records in a descending order, you can use the
  • By default, it’s ascending order

Query –

select Salary from employee order by Salary Order By




select Emp_ID,FirstName,LastName,Department,Mobile_No,Salary,Address from employee order by Salary

Order By Data


What is V-model and advantages and disadvantages of this model

What is V-model ?

– V- model means Verification and Validation model.
– Each phase must be completed before the next phase begins.
– Testing of the product is planned in parallel with a corresponding phase of development.

V- Model Design and Flow-

V model has the different phases as shown in the above diagram.

Advantages of V-model:

  • Simple and easy to use.
  • Testing activities like planning test designing happens well before coding. This saves a lot of time. Hence higher chance of success over the waterfall model.
  • Proactive defect tracking – that is defects are found at early stage.
  • Avoids the downward flow of the defects.
  • Works well for small projects where requirements are easily understood.

Disadvantages of V-model:

  • Very rigid and least flexible.
  • Software is developed during the implementation phase, so no early prototypes of the software are produced.
  • If any changes happen in midway, then the test documents along with requirement documents has to be updated.