> For the complete documentation index, see [llms.txt](https://upsolver.gitbook.io/content/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://upsolver.gitbook.io/content/reference-1/functions-and-operators/functions/conditional.md). # Conditional This section describes the following conditional functions:

Function	Description
COALESCE	Returns the first input that is not null. If an input is an array, the whole array is returned. Empty arrays are not selected and are considered to be equivalent to a null value.
IF_ELSE	If there is a `true` Boolean value in the `condition` parameter, then return the second argument. In all other cases, return the third argument
NULL_IF	If there is a `true` Boolean value in the `condition` parameter, then return null. Otherwise, return the second argument

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