Does qv has restrictions about field length (BLOB TYPE)

[WorkFish]

Hi  Guys

i write a sql script which include BLOB type fields ,and  the maximum length of BLOB type field is about 50,000,000 .

after loading i create a table box to see whether it can show correctly or not .

some can be shown , and  some are empty  status which i think are those has long long length value.

so is it too long that can't show up in the qv or has other reason that i don't know?

Please tell me if you know the answer.

Thanks in advance.

[marcus_sommer]

AFAIK there are no limitations unless 2 billion distinct field-values for a field and everything else is just restricted through the available hardware. In regard to viewing the data per access point there might be further limitation through the used html/js especially in regard to timeouts if the rendering takes too long.

More likely will be that your used driver has any limitations. Beside this does it make really sense to view any blob-content within a table-cell?

- Marcus

[WorkFish]

i doubt it too but it's user's requirment.they need to use this field to view log data. 

[marcus_sommer]

Log data means this field doesn't contained binary stuff else string-values, right? In this case you could try to cast this field to a varchar.

- Marcus

[WorkFish]

It stored in hexadecimal format.    'Cast blob to varchar' you mean write in sql or ? But it seems don't work in Oracle .I use to_char() it turns out error and use dbms_lob.substr() which only convert 2000 characters at a time.

Couldn't find a way to show this field perfectly.

[marcus_sommer]

Yes, I meant to do it within the sql-query but I couldn't give hints which functions would be suitable. Beside this you could try to measure the length (also within the sql-query) to see it more detailed until which length it worked and where not respectively if this doesn't matter at all and any other reason caused the issue.

- Marcus