How do I store image sequence changes to a mysql database with php

Question

I am trying to build a photo organization table and am looking for advice and/or examples of how to save the display sequence of photos to a database. I'm using php and mysql

Example: If I have 10 photos in an album and decide to change the sequence of images, so I move a photo from seq 2 to seq 7, then the sequence changes to the following.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10 Original Sequence

1, 7, 2, 3, 4, 5, 6, 8, 9, 10 New Sequence

How do I tell the database that the sequence column for all the affected rows has changed? ...in one operation.

Do I change multiple rows in the db at once? Can I limit to just the affected rows

the photos table currently has "rowID, sequence, URL...."

Answer 1

Consider having the same Sequence in the database and rather than changing sequences inside database overwriting it all the time, use a php random generator like so:

$db=new SQLite3("sqlite.db") or die ("Your Internet Connection Dropped!");
$select_table = $db->query("SELECT * FROM images"); 
while($image=$select_table->fetchArray(SQLITE3_ASSOC)){
  echo "<img src='path/to/file/".$image[rand(1,11)].".png'>";
}

My Code is bad in security, but It should do the job, Hope it helps!

Answer 2

UPDATE table SET display_order = CASE WHEN id=first_id THEN second_order ELSE first_order END WHERE id = first_id OR id = second_id LIMIT 2

在您具有first_id，first_order，second_id，second_order的位置，这将切换其显示顺序。

Answer 3

您也可以只将表写入具有next_image_id和previous_image_id的内容，这样插入图像所需要做的就是更改先前的图像next_image_id和下一幅图像的previous_id以及同一图像。