OBI precision lost while drilling

Question

Hello,
I would like to ask experts if any of you encounter problem with precision being lost while drilling.
Environment:
MSSQL database
OBI 11.1.1.6.0
I've created measure (let's call it "ab") which is adding two other logical measures (a + b).
"ab" logical column is nullable with formula: "case when a is null and b is null then null else ifnull(a, 0) + ifnull(b, 0) end"
When I'm drilling location dimension from level X to Y (lower) precision for ab measure is being lost.
Source of that problem is SQL phrase convert( REAL , NULL ) which OBI is generating for DOUBLE PRECISION logical column (ab).
At the end of SQL statement when all location levels are folded OBI is providing statement which is limiting precision
case when convert( REAL , NULL ) is null and D1.c1 is null then NULL else isnull(convert( REAL , NULL ) , 0.0) + isnull(D1.c1 , 0.0) end as c14
Column c1 in statement above is DECIMAL(20,2) type.
Could you please provide any workaround for this?
PS. I've created service request but 6 months of no resolution so I hope to get some workaround here :).
Regards,
Lucas

Answer 1

thanks for answer, but it's not the case.
For example on Europe level I'm getting 123'456'426.8 value and after drill down I'm getting 123'456'432.0 (also for Europe) because of precision truncate in database query. Precision is changed because of convert( REAL , NULL ) statement.
When I run same as OBI physical query with convert( REAL , NULL ) changed to convert( FLOAT , NULL ) values are correct.
Lucas