Can you use or in a CASE statement?

Can you use or in a CASE statement?

In this blog post we will see a question asked for one of my friends in the interview about How to use OR condition in a CASE WHEN statement. It is practically not possible to use OR statement in CASE statement as the structure of the CASE statement is very different.

What are the two types of CASE expressions?

There are two forms of case expressions:

• • Simple.
• Syntax for the searched case expression is as follows:
• Operand type and Result type: All data types, but the types of source_value,match_value1, match_value2, …
• ‘unknown’) AS state_name;
• and.

How do you use and in a CASE statement?

The SQL Server CASE Statement consists of at least one pair of WHEN and THEN statements. The WHEN statement specifies the condition to be tested. The THEN statement specifies the action if the WHEN condition returns TRUE. The ELSE statement is optional and executes when none of the WHEN conditions return true.

Which operator allows multiple values in where clause?

The SQL IN Operator
The SQL IN Operator The IN operator allows you to specify multiple values in a WHERE clause. The IN operator is a shorthand for multiple OR conditions.

What does a case statement do?

The CASE statement chooses from a sequence of conditions, and executes a corresponding statement. The CASE statement evaluates a single expression and compares it against several potential values, or evaluates multiple Boolean expressions and chooses the first one that is TRUE .

What is the use of CASE in SQL?

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. It can be used in the Insert statement as well.

When to use a case expression in a statement?

The CASE expression evaluates a list of conditions and returns one of the multiple possible results. You can use a CASE expression in any statement or clause that accepts a valid expression.

How is the search case expression used in Oracle?

In other words, Oracle evaluates each Boolean condition to determine whether it is true, and never evaluates the next condition if the previous one is true. When you use the searched CASE expression within a SELECT statement, you can replace values in the result based on comparison values.

How does the database evaluate a case expression?

For a searched CASE expression, the database evaluates each condition to determine whether it is true, and never evaluates a condition if the previous condition was true.

When to omit the else clause in a case expression?

If you omit the ELSE clause and no Boolean expression evaluates to true, the CASE expression returns a NULL value. The following illustrates the searched CASE expression example. If the salary is less than 3000, the CASE expression returns “Low”. If the salary is between 3000 and 5000, it returns “average”.