sleep thread process

$str = 'w0';
for($w=0;$w<999999;$w++){
    $sql = 'INSERT INTO w1 (wint,wchar) VALUES ('.$w.',"'.$str.'")';
    mysqli_query($link,$sql);

}

$str = 'w1';
for($w=1000000;$w<1999999;$w++){
    $sql = 'INSERT INTO w1 (wint,wchar) VALUES ('.$w.',"'.$str.'")';
    mysqli_query($link,$sql);

}

 

$str = 'w0';
for($w=0;$w<60;$w++){
    $sql = 'INSERT INTO w1 (wint,wchar) VALUES ('.$w.',"'.$str.'")';
    mysqli_query($link,$sql);

}

$str = 'w1';
for($w=100;$w<160;$w++){
    $sql = 'INSERT INTO w1 (wint,wchar) VALUES ('.$w.',"'.$str.'")';
    mysqli_query($link,$sql);

}

$str = 'w1';
for($w=100;$w<160;$w++){
    $sql = 'INSERT INTO w1 (wint,wchar) VALUES ('.$w.',"'.$str.'")';
    mysqli_query($link,$sql);
    sleep(1);
}

$str = 'w0';
for($w=0;$w<60;$w++){
    $sql = 'INSERT INTO w1 (wint,wchar) VALUES ('.$w.',"'.$str.'")';
    mysqli_query($link,$sql);
    sleep(1);
}