OLEDB read failed

[#1]

Hi Folks,

I have an oracle query that runs fine in TOAD but when I try to run it in Qlikview I get the error "OLEDB read failed". The connection string is fine as I can run other queries against in the same application. Has anyone seen this error before and if so did you find a solution.

Thanks and Regards,

Footsie

[#2]

can you post the query,

Large part of the time , it is due to a mismatch between the SQL sentence and the LOAD sentence.

Thanks

Philippe

[#3]

Hi, I meet the same error these days. It spent me 5days to find the solution...Still no answer. I find out if I load some of data it's ok , but failed in some certain record. And I focus on such a record which has some field's value is strange ,not stardard character. And if I jump the record it's ok. But I still don't know how could I read these strange character.

[erichshiino]

Hi, Footsie. It happened to me before when I got some functions that run on toad, but somehow were not recognized through OLEDB connection (I believe it was a limitation on the driver because I got problems with different fuctions using different drivers).

So, to proceed I'd like to take a look at the fuctions you are calling on select statement.

Philippe post also makes sense because the sql query can accept some structures that QV can't. For example, you could call the same field twice, or rename two fields to have the same name and then on a Load *; you will get a problem.

Sometimes, you can try to use another driver (if it's available) to check if you get the same error.

Hope it helps,

Erich

[#5]

I had the same issue with one of the SQL query and I've managed to resolve it by making sure all the column names have valid names defined (ex: select count(*) as 'colum name' ....).

[#6]

Based on my experience OLEDB read failed is caused by duplicate column name, check whether all columns have different names then reload.

ex:

select

date,

column1,

timestamp(date) as date

from table1

[#7]

Hi,

I am also facing the same problem from a number of days.  The most confusing thing is, the same query once fails due to OLEDB read failed, and runs successfully in the next run. I checked and found no error in the DB side.

There are no duplicate field names in my query. I ensured it with priority.

@ Philippe : Could you please explain, what you meant, when you said

"Large part of the time , it is due to a mismatch between the SQL sentence and the LOAD sentence."

[#8]

Try to reduce the table to 1field . Then load the table. If no error,add 1 field, load table of 2 fields. If no error add other field until you get an error. Then you will focus on which field make the error. I think some field make the oledb error. Delete the field or do something else to make it correct.

发自我的 iPad

[#9]

Hi,

Many thanks for your reply.

The main problem is I am not experiencing this error everytime I am

reloading the application. Suppose if I receive the OLEDB read failed

error at a time, the same application is reloaded successfully after 10

minutes.

Also the case is not for only one application, I am receiving this error

for the applications fetching data from many Databases at different times.

I also checked for logshipping or any workflow running in the DB side, but

there also I found nothing suspicious.

Could you kindly let me know your comment on the same.

Sayak Roy

Tata Consultancy Services

[#10]

Hi,

I checked the timing of the failed part of the Query and the same Query on

any successful day, but I couldn't find any such difference in time by

which we can get sure of it.

The failed part of the Query naturally takes lesser time to get reloaded

than the successful one.

"Once I notice the error occurs because of some records"

Can you please tell me whether you are saying about any particular

datatype.

Sayak Roy

Tata Consultancy Services