Update multiple rows using single query in JDO - sql

Question

Iam having a table like this
SorOrder Name Date
1 Image1 5/6/15
2 Image2 6/8/16
3 Image3 6/8/16
4 Image4 9/8/16
..........
Now if iam deleting image2 i want to udate the table so that the sortorder
again is in ordered form like this
Updated Table :
SorOrder Name Date
1 Image1 5/6/15
2 Image3 6/8/16
3 Image4 9/8/16
..........
SO how to make it posible??
This is the class for the table Images:
public class Images extends ApplicationEntity{
#Column(name="PROFILE_ID", allowsNull="false")
private Profile profile;
private int sortOrder;
private boolean active;
private Date deletedDate;
public Images (){
super.setEntity("Images ");
}
public Images (Profile profile, int sortOrder, boolean active,
Date deletedDate) {
super();
this.profile = profile;
this.sortOrder = sortOrder;
this.active = active;
this.deletedDate = deletedDate;
}
public Profile getProfile() {
return profile;
}
public int getSortOrder() {
return sortOrder;
}
public void setSortOrder(int sortOrder) {
this.sortOrder = sortOrder;
}
public boolean isActive() {
return active;
}
public void setActive(boolean active) {
this.active = active;
}
public Date getDeletedDate() {
return deletedDate;
}
public void setDeletedDate(Date deletedDate) {
this.deletedDate = deletedDate;
}
#Override
public String toString() {
return "Images [profile=" + profile + ", sortOrder=" + sortOrder
+ ", active=" + active + ", deletedDate=" + deletedDate + "]";
}
}
I tried this query: String query = "update Images set SORTORDER =((SELECT selected_value FROM (SELECT MAX(SORTORDER) AS selected_value FROM Images where ACTIVE = 0 && PROFILE_Id="+profileId+") AS sub_selected_value) + 1) where PROFILE_Id="+profileId;
But it updates all the sorOrder to same value.
I was using this code to update the sortorder:
int sortoder=1;
for (Images file : imagesListFromDB) {
file.setSortOrder(sortOrder);
sortOrder++;
}
But it takes more time,if iam having 8000 images then its really slow.SO i thought of updating in a single query. But not getting any idea

Answer 1

To do in a single statement you could make use of SQL. Here are a couple of ideas (adapt to your use-case) - you use the "?" parameter to set the position above what you delete.
UPDATE IMAGES SET SORTORDER =
(CASE WHEN (SORTORDER <= ?) THEN SORTORDER
ELSE (SORTORDER-1) END)
Or
UPDATE IMAGES SET SORTORDER = SORTORDER-1
WHERE SORTORDER > ?
Using DataNucleus JDOQL UPDATE extension you could do this (and set the parameter "param" to the sortOrder start point to update
pm.newQuery("UPDATE mydomain.Images SET this.sortOrder=this.sortOrder-1 WHERE this.sortOrder > :param");