Checks from left to right for the first non-NULL argument found for each entry parameter pair.

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Syntax

COALESCE(<expression> [,...])

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Parameters

ParameterDescriptionSupported input types
<expression>The expression(s) to coalesce.Any

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Return Types

Same as input type

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Example

The following example returns the first non-NULL value provided, which is the username esimpson: 
SELECT COALESCE(NULL, 'esimpson','sabrina21') AS nicknames;
Returns: esimpson