MySql Query: PLSQL Conditions within query

Suppose we have a table like:

 

  
transaction_id
  
acc_no
  
amount
 
 

  
1
  
100001
  
20000
 
 

  
2
  
100002
  
30000
 
 

  
3
  
100003
  
30000
 
 

  
4
  
100004
  
10000
 
 

  
5
  
100005
  
50000
 

Now the query

select
    acc_no,
    SUM(IF(amount>20000,amount,0)) as total_value
from
    account
where
    acc_no=100002
group by acc_no;

will produce the following result:

 

   

      
acc_no
      
amount
   
   

      
100002
      
80000
    

Case statements can also be used within a query like shown in the answer of this stackoverflow question