我有一个工作脚本,用于选择所有表中的图像字段并在物理文件不存在时清空它们的值。优化PHP脚本
$query1 = "SELECT table_name,column_name
FROM information_schema.columns
WHERE table_schema='schemaname' AND column_name like '%image%' or column_name='video'";
$result1 = mysql_query($query1) or die(mysql_error() . " -- " . $query1);
while($row1 = mysql_fetch_row($result1)){
if (!strpos($row1[0],'backup') > 0){
$sql = "Select COLUMN_NAME FROM information_schema.columns WHERE TABLE_NAME = '".$row1[0]."' AND EXTRA = 'auto_increment'";
$resultcol = mysql_query($sql);
$rowcol = mysql_fetch_row($resultcol);
$query2 = "SELECT " . $row1[1] . ", " .$rowcol[0] . "
FROM " . $row1[0] . "
WHERE " . $row1[1] . " != '' AND " . $row1[1] . " IS NOT NULL
";
echo $query2 . "<br>";
$result2 = mysql_query($query2) or die(mysql_error() . " -- " . $query2);
while ($rowdb = mysql_fetch_row($result2)){
if (!strpos($rowdb[0],'facebook') > 0 && !file_exists($img_root.'/'.$rowdb[0])){
$sql = "UPDATE ".$row1[0]." SET ". $row1[1] . " = '' WHERE " . $rowcol[0]. "= ".$rowdb[1];
echo $sql . "<br><br>";
$delete_count++;
//mysql_query("UPDATE ".$row1[0]." SET ". $row1[1] . " = '' WHERE id = ".$row1["id"]);
}
}
}
}
脚本工作正常,但需要时间,虽然,我不知道是否有一个更聪明的方式(更优化),以获得相同的功能?谢谢
http://codereview.stackexchange.com/ – j08691
这个问题似乎是题外话,因为它属于为http://代码审查.stackexchange.com/ –
您可以使用JOIN将前两个查询合并到一个查询中。 – Barmar