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Edu Jr Haban
Last answered:

31 Aug 2022

Posted on:

22 Oct 2021

1

how can you apply primary keys in multiple columns

in SQL / Relational schemas - Unique key and null values
3 answers ( 0 marked as helpful)
Martin Ganchev
Instructor
Posted on:

24 Oct 2021

2
Anuradha Perumal
Posted on:

29 Aug 2022

0
Tsvetelin Tsonkov
Instructor
Posted on:

31 Aug 2022

1

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can we write the query like this:

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