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<?php $sample = array('a.col1','a.col2','b.col1','c.col1','c.col2','d.col5'); array_walk($sample, function($v) use (&$r){ $arr = explode('.', $v); $alias = isset($arr[0]) ? $arr[0] : ''; $r[$alias][] = isset($arr[1]) ? $arr[1] : ''; }); extract($r); print_r($a);

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