Query prefix error

[mjjuk]

Hi All, 

I get an error intermittently when quering tables for instance 

Select * FROM a.table1;

the result is 

a.column1

a.column2

a.column3 ...... etc 

On occasions it will run a refresh and it no longer shows the prefix witch messes up the querys 

so I end up with 

column1

column2 

column3 

and potentially vice versa ... why does this happen?

[v-piga-msft]

Hi @mjjuk ,

I have a little confused about your scenario.

Do you mean that you do not have all of the data when it has refresh in power bi desktop?

Do you get any error message?

Best Regards,

Cherry

[mjjuk]

Hi, sorry it’s difficult to explain.
Any expressions or power query steps are written with the prefix a.column1 and when the refresh is run the error is that it can’t find the column (as it is now called just column1)
If this makes more sense

[mjjuk]

I am not sure if I can explain this in another way that will make more sense 🙂

If I have a query in PBI, for example

SELECT

a.jobnumber,

a.name,

a.address,

a.postcode,

a.visits,

a.duration

FROM database_history.customer_tables

I would expect the table to retain the prefix so the column names would be:

a.jobnumber | a.name |  a.address | a.postcode | a.visits | a.duration

I have some applied steps which transforms some of the data but it will not work because the additional steps are like below:

= Table.TransformColumnTypes(Source,{{"a.visits", Int64.Type}, {"a.duration", Int64.Type}})

for some reason the PBI has removed the "a." prefix from the table and now I get the error

"a.visits not found"

It would be straight forward to change all the applied steps to get this to work but this also has a knock on affect to the main report and there are loads of them in the actual report that would need changing accross multiple queries ..... and once done what if all of a sudden the prefixes are returned and I would have to add them back in ... its so fustrating !