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Invalid BLOB handle in record buffer
Hi,
I am using a TTable component in Delphi 7 to access a table that has BLOB fields. As I navigate around the table I get an invalid BLOB error. I understand why I get the error, the fact being that it caches the BLOB fields and when I go back too many records, the BLOB handle is invalid. I don't want to just increase the number of BLOBs that are cached.
My question is, how can I code my program so that as I move around it doesn't try and use a cached BLOB, but always loads a new BLOB? I was thinking that maybe I could use an event handler somehow to do this.
Regards,
Bill
I am using a TTable component in Delphi 7 to access a table that has BLOB fields. As I navigate around the table I get an invalid BLOB error. I understand why I get the error, the fact being that it caches the BLOB fields and when I go back too many records, the BLOB handle is invalid. I don't want to just increase the number of BLOBs that are cached.
My question is, how can I code my program so that as I move around it doesn't try and use a cached BLOB, but always loads a new BLOB? I was thinking that maybe I could use an event handler somehow to do this.
Regards,
Bill
Rather than using a TTable, consider using a TQuery and set RequestLive=True if possible. Blobs to Cache BDE parameter is not used when using this method.
Hope this helps
Floyd
Hope this helps
Floyd
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Loading the blob on a second dataset worked. However, the report did not print the blob although the preview displayed it. How can this happen?
I followed Meikl's solution on using another dataset for the blob. At first it was working and then after more tests of saving records using two datasets, I encountered it again. Any more ideas?
The problem got solved by setting the BLOBS TO CACHE to -1, not in the BDE but within the program.
No comment has been added lately, so it's time to clean up this TA.
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to accept grolschisgood's answer
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kacor
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I will leave a recommendation in the Cleanup topic area for this question:
to accept grolschisgood's answer
Please leave any comments here within the next seven days.
PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!
Some days and here is the Christmas Time. I wish good luck and good health for you all and for your loved ones
kacor
EE Cleanup Volunteer
load your blob separatly in a second dataset in the aftersroll event of the primary (blobless) dataset
just as suggestion if possible
meikl ;-)