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$cond (aggregation)

$cond (aggregation)¶

$cond¶

Use the $cond operator with the following syntax:

{ $cond: [ <boolean-expression>, <true-case>, <false-case> ] }

Takes an array with three expressions, where the first expression evaluates to a Boolean value. If the first expression evaluates to true, $cond returns the value of the second expression. If the first expression evaluates to false, $cond evaluates and returns the third expression.

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