PL/SQL - Nested IF-THEN-ELSE Statements

PL/SQL - Nested IF-THEN-ELSE Statements

One if condition with in another if condition is known as nested if.
Syntax:

IF( Condition 1)THEN 
    ...
    ...
   IF(Condition 2) THEN 
    ...
    ...
   ELSE
     ....
     ....
   END IF; 
ELSE 
   ...
   ....
   
END IF; 

Example #1

DECLARE 
   c_id customers.id%type := 3; 
   c_sal  customers.salary%type; 
BEGIN 
   SELECT salary INTO c_sal
   FROM customers
   WHERE id= c_id;  
   if(c_sal>=1000 and c_sal<=2000) then
   update customers set salary=c_sal+100 where  id= c_id; 
  elsif(c_sal>=3000 and c_sal<=6000) then
   update customers set salary=c_sal+200 where  id= c_id; 
  elsif(c_sal>=7000 and c_sal<=10000) then
   update customers set salary=c_sal+500 where  id= c_id; 

   else
   update customers set salary=c_sal-1000 where  id= c_id; 
end if;
   
END; 
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