How do I use a CASE statement in SQL Developer?

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.

What does a CASE statement do in SQL?

The SQL CASE Statement 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.

Where do you put CASE statements in SQL?

Using CASE statements with the ORDER BY clause SQL queries use the ORDER BY clause for data sorting in either ascending or descending order. You can use the CASE statements in conjunction with the ORDER BY clause. Suppose from the products table, we retrieve the [ProductName] and [ListPrice].

How does a CASE statement execute?

The CASE statement selects a sequence of statements to execute. To select the sequence, the CASE statement uses a selector (an expression whose value is used to select one of several alternatives) or, in the searched CASE statement, multiple search conditions.

What is case statement explain with example?

A CASE statement is similar to IF-THEN-ELSIF statement that selects one alternative based on the condition from the available options. CASE statement uses “selector” rather than a Boolean expression to choose the sequence. The value of the expression in the CASE statement will be treated as a selector.

What is case in SQL Oracle?

Oracle CASE expression allows you to add if-else logic to SQL statements without having to call a procedure. 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 are case statements evaluated in SQL?

The CASE expression evaluates its conditions sequentially and stops with the first condition whose condition is satisfied. In some situations, an expression is evaluated before a CASE expression receives the results of the expression as its input. Errors in evaluating these expressions are possible.

What is CASE statement in PL SQL?

The PL/SQL CASE statement facilitates you to execute a sequence of satatements based on a selector. A selector can be anything such as variable, function or an expression that the CASE statement checks to a boolean value. The CASE statement works like the IF statement, only using the keyword WHEN.

How is a case statement evaluated in SQL?

What is case structure in programming?

A Case Structure is a branching control mechanism that allows different executions depending on the value of the label. The Case Structure is analogous to the Case block in Java or C++ in which, based on what case value the input variable matched, the case structure will choose the correct cases for execution.