have you tried using DOT_UID as Image Primary Key Column instead? The reason for that is that when we read the image we are executing the base SQL statement of the List View and restrict it with the Image PK column = current value of row. If you use IMAGE_UID and it isn't unique within that SQL statement you would be in trouble.
BTW, I did a simple test before on DEMO_PRODUCT_INFO which contains a blob and it worked fine. Can you confirm that a simple test case also works for you?
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Thanks for looking at this with me. I tried the DOT_UID and also a test using DEMO_RPODUCT_INFO and still did not get the image to show.
with DOTS as (
select 12 as DOT_UID,'Item 1' as DOT_NAME,90 as GREEN,70 as YELLOW,70 as RED, 1 as CURRENT_DOT from dual
select 13,'Item 2',90,70,70,1 as CURRENT_DOT from dual
select 15,'Item 3',90,70,70,1 as CURRENT_DOT from dual
select 17,'Item 4',101,90,80, 4 as CURRENT_DOT from dual
select 22,'Item 5',95,85,85,1 as CURRENT_DOT from dual)
D.CURRENT_DOT = I.PRODUCT_ID;
If I simply do this it works: