Add rows for each date using values from another table
I have 2 tables as shown.
For each date, I want to have a row containing each unique value of table2 field1. In table1, on 1/7/2021, field1 has value A, B and C are missing. On 2/7/2021, field1 has values A and B, C is missing. The final table I am looking for is as below where the highlighted rows are the missing rows I want to add in.
Any suggestions on how I can achieve this in my load script? Thanks.