How do you write a CASE statement in select query in Oracle?
Your SQL statement would look as follows: SELECT table_name, CASE owner WHEN ‘SYS’ THEN ‘The owner is SYS’ WHEN ‘SYSTEM’ THEN ‘The owner is SYSTEM’ END FROM all_tables; With the ELSE clause omitted, if no condition was found to be true, the CASE statement would return NULL.
Can we use select query in CASE statement?
The case statement in SQL returns a value on a specified condition. We can use a Case statement in select queries along with Where, Order By, and Group By clause. Once a condition is satisfied, its corresponding value is returned.
Can we write select statement in if condition in Oracle?
The syntax for IF-THEN-ELSIF in Oracle/PLSQL is: You use the IF-THEN-ELSIF syntax, when you want to execute one set of statements when condition1 is TRUE or a different set of statements when condition2 is TRUE.
Can we write CASE statement in where clause?
CASE STATEMENT IN WHERE CLAUSE: We can use a case statement in Where, Order by and Group by clause. So, by using a CASE statement with the where condition displays the result.
How does a case statement work?
The CASE statement goes through conditions and returns a value when the first condition is met (like an if-then-else statement). So, once a condition is true, it will stop reading and return the result. If no conditions are true, it returns the value in the ELSE clause.
How many else clauses can an if statement have Mcq?
The IF statement can have multiple ELSIF parts but can have only one ELSE statement part. ELSE part will be executed after each of the ELSIF part is checked and found to be FALSE.
How many types of IF statements are there?
There are three forms of IF statements: IF-THEN , IF-THEN-ELSE , and IF-THEN-ELSIF .
Can CASE statement be used in where clause?
CASE STATEMENT IN WHERE CLAUSE: The CASE statement returns the value based on condition. We can use a case statement in Where, Order by and Group by clause.
