Setting PHP Variable if condition

I'm creating a function that has to check for several inputs and create a variable that I use to call a SQL query, the problem I'm facing is that I want to change a variable so that I don't use the SELECT call every time, but instead the AND call. How does one construct such a function? This is what I currently have.

if ($_GET['filtering2'] != "" || $_GET['filtering3'] != "" || $_GET['filtering4'] != "" || $_GET['filtering5'] != "" || $_GET['filtering6'] != "" || $_GET['filtering7'] != "" || $_GET['filtering7'] != "") {

    function searchByColumn($values, $columnName)
    {
        $string = implode(" OR season LIKE ", $values);
        if ($firstTime = 2) {

            return "SELECT * FROM shrubs2 WHERE season LIKE $string";

        } else {
            return " AND WHERE season LIKE $string";
        }
    }

    $colNames = array("season"); // can add here more column names
    foreach ($colNames as $colName) {
        $str .= searchByColumn($array_name, $colName);
        $firstTime = 3;
    }
}
if ($_GET['filtering8'] != "" || $_GET['filtering9'] != "" || $_GET['filtering10'] != "" || $_GET['filtering11'] != "") {

    function searchByColumn2($values, $columnName2)
    {
        $string2 = implode(" OR 日照 LIKE ", $values);
        if ($firstTime = 2) {
            return "SELECT * FROM shrubs2 WHERE 日照 LIKE $string2";

        } else {
            return " AND WHERE 日照 LIKE $string2";
        }
    }

    $colNames2 = array("日照"); // can add here more column names
    foreach ($colNames2 as $colName2) {
        $str .= searchByColumn2($array_name2, $colName2);
        $firstTime = 3;
    }

}

I was trying to change the variable $firstTime, but it never resulted as I wished for it to do.