Wrong Data count of Left outer Join between 2 tables

[#1]

Hi All,

I have created Calculation View and considered 2 tables inside projections and joined them with Left outer join.

Data count of Left side Table: 51731

Data count of right side table: 3760

Type of join: Left outer Join

There is a join (Left Outer join) condition between two tables based on Document Number.

But out put of join is not matching with data count of Left side table which is 51731. It is giving more records (64874) than actual (51731).

What would be the reason? 

What I should do to get correct count .

Are primary key combination should match between two tables?

Thanks in Advance.

[muthuram_shanmugavel2 · Accepted solution]

Hi Ram,

The problem happened due to duplicate Entries in Projection_3 Node.

WORKCENTER and PRODORDER column have multiple values for same DOC_NUMBER, MATERIAL and MAT_PLANT fields.

For example your data is like in Projection_3 Node

If your Projection_1 Node have only 1 row with (1, MAT_A and BLR entries), By Performing this LO Join Operation It will have Join Output as 3 rows.

I hope you could get the cause of the problem.

To avoid this Problem,

Make sure you have unique Entries (By 3 columns combination) in Projection_3 node.

You can use Filter operation or Latest_Time stamp operation to get the unique count of records.

Best Regards,

Muthu