XML XQuery If Then Else

• The If Then Else statement is used for conditional execution of statements in XQuery.
• The statements are executed based on the evaluation of a specified Boolean expression.

Syntax

if (boolean-expression)
then expression
else expression

Example

let $num:= 5
return
if($num > 0) then "Positive"
else "Negative"

Output

Positive

Explanation

In the above example, the If Then Else statement checks whether the value of the $num variable is greater than 0. If the condition is true, the expression "Positive" is returned as the output. Otherwise, the expression "Negative" is returned as the output.

Use

The If Then Else statement is used when we need to perform different actions based on a condition. It can be used in various scenarios such as data filtering, data transformation, and data validation.

Important Points

• The If Then Else statement is always evaluated as a Boolean expression.
• Only one of the two expressions will be executed based on the evaluation of the condition.
• The If Then Else statement can be nested within another If Then Else statement to create complex conditions.

Summary

In XQuery, the If Then Else statement is used for conditional execution of statements. It evaluates the specified condition and executes the corresponding expression. This statement is useful in various scenarios such as data filtering, data transformation, and data validation. It can also be nested within another If Then Else statement to create complex conditions.