An Ampersand (&) before a function means? [duplicate]

This question already has answers here: 开发者_如何学Go What does it mean to start a PHP function with an ampersand? (3 answers) Closed 7 years ago.

I know & is used to create references.

But I wonder what having a & before a function name means:

function &DB($params = '', $active_record_override = FALSE) { // code }

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It returns the result by reference. See the manual entry for it here.