The City Council yesterday overrode Mayor Bloomberg’s veto of a union-backed bill requiring non-union developers on affordable-housing projects to provide quarterly-wage and other data.

The vote was unanimous — 46-0.

Aides said the mayor was disappointed and considering suing to block the law from taking effect. He’d argued that this would be an unnecessary and costly burden to the city and small developers who have angered construction unions by not employing their members.

But City Council Speaker Christine Quinn cited “horror stories” of residents who had bought poorly constructed “affordable” homes.

“I just don’t know why you don’t want to have that information out there,” she said.