Update error from alpha4 to alpha5

    * user warning: Can't DROP 'PRIMARY'; check that column/key exists query: ALTER TABLE image_attach DROP PRIMARY KEY in /var/www/html/drupal/includes/database.mysql-common.inc on line 386.
    * user warning: Can't DROP 'iid'; check that column/key exists query: ALTER TABLE image_attach DROP INDEX iid in /var/www/html/drupal/includes/database.mysql-common.inc on line 448.
    * user warning: Can't DROP 'PRIMARY'; check that column/key exists query: ALTER TABLE image DROP PRIMARY KEY in /var/www/html/drupal/includes/database.mysql-common.inc on line 386.
    * user warning: Can't DROP 'image_fid'; check that column/key exists query: ALTER TABLE image DROP INDEX image_fid in /var/www/html/drupal/includes/database.mysql-common.inc on line 448.

Here is the update query output:

The following queries were executed
image_attach module
Update #6100

    * ALTER TABLE {image_attach} CHANGE nid `nid` INT unsigned NOT NULL DEFAULT 0
    * ALTER TABLE {image_attach} CHANGE iid `iid` INT unsigned NOT NULL DEFAULT 0
    * Failed: ALTER TABLE {image_attach} DROP PRIMARY KEY
    * ALTER TABLE {image_attach} ADD PRIMARY KEY (nid)
    * Failed: ALTER TABLE {image_attach} DROP INDEX iid
    * ALTER TABLE {image_attach} ADD INDEX iid (iid)

image module
Update #6100

    * ALTER TABLE {image} CHANGE nid `nid` INT unsigned NOT NULL DEFAULT 0
    * ALTER TABLE {image} CHANGE fid `fid` INT unsigned NOT NULL DEFAULT 0
    * Failed: ALTER TABLE {image} DROP PRIMARY KEY
    * ALTER TABLE {image} ADD PRIMARY KEY (nid, image_size)
    * Failed: ALTER TABLE {image} DROP INDEX image_fid
    * ALTER TABLE {image} ADD INDEX fid (fid)

Update #6101

    * No queries

Update #6102

    * No queries

This happens on three sites I'm updating. All still work fine afterward.