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Anonymous
Not applicable

Relationship between Calendar table with other tables

I have 3 tables (Headcount, Separations and Calendar) i want to make a relationship of both headcount and separations with a Calendar table. beacuase i want to see the separation and headcount numbers of 2015, 2016. BUT i am unable to connect these three table (I AM JOINING MONTHS COULMNS). Following error is appearing while joining the tables.

 

Untitled3333.png

 

Please help...

1 ACCEPTED SOLUTION
v-ljerr-msft
Microsoft Employee
Microsoft Employee

Hi @Anonymous,

 

Basically what that error is complaining about is that the relationship you're trying to create from your tables has issue: One of the Month columns must have unique value of month. You can't have Many to Many relationship but only One to Many or Many to One relationship between them.

 

In your scenario, I would suggest you to create a new Month table(acts as a middle table) which only contains one column of unique value of month. And first relate your Calendar table to the Month table with the month column, then relate the Month table to Headcount, Separations table.Smiley Happy

 

middletable1.PNG

 

Regards

View solution in original post

1 REPLY 1
v-ljerr-msft
Microsoft Employee
Microsoft Employee

Hi @Anonymous,

 

Basically what that error is complaining about is that the relationship you're trying to create from your tables has issue: One of the Month columns must have unique value of month. You can't have Many to Many relationship but only One to Many or Many to One relationship between them.

 

In your scenario, I would suggest you to create a new Month table(acts as a middle table) which only contains one column of unique value of month. And first relate your Calendar table to the Month table with the month column, then relate the Month table to Headcount, Separations table.Smiley Happy

 

middletable1.PNG

 

Regards

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