Power App - Using gallery with relational tables with Lookup tables

[WillieEra]

I am building an app that has a transaction table with customer_id, then a customer table with customer_id and customer_name, when I create a gallery to view the cards I get the Customer_ID as 1, I then go to the datacardvalue and select Text = Lookup(customer table, customer_id = customer_id, customer_name)

The result is that the first displayed card shows the customer name, however where the ID changes to another customer at the next card it still carries the first customer name.

There are no errors shown.

[mdevaney]

@WillieEra 

The reason you are always returning the first result no matter what is because of this code.

customer_id = customer_id

This code says compare the customer_id of the record in Customer table to itself.  Therefore it will always evaluate to true.  Since LookUp returns the first result with a true condition the top row of your table will always be returned.

Try this: it will look for the customer_id of the current record in the gallery instead.

Lookup(customer table, customer_id = ThisItem.customer_id, customer_name)

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[WillieEra · Accepted solution]

Thank you for the quick feedback, I did what you suggested:

Text = LookUp('[dbo].[cust_dim_tbl]', Client_ID= ThisItem.Client_ID, Customer_Name)

On my SQL tables there are different ID's to different users and in the main table there are different ID numbers showing.

[WillieEra]

Your suggestion made me think, so I went to change the field names in one of the tables to Customer_ID_Key and redid the formula, it worked. Thank you for the help!