Can unique keys hold null?

In the case of a primary key, we cannot save NULL values. In the case of a unique key, we can save a null value, however, only one NULL value is supported.

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2024-01-10 11:23:55

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How many games can a ps5 digital hold?
Many of the best PS5 games require between 40-60 GB of storage. Even if you mix in some PS4 games and smaller indies, you can realistically store 10-15 games on the drive at a time.
2023-12-22 22:16:07

Are uk steam keys region locked?
In most cases, there are no region restrictions on products purchased directly from the Steam store. However, products purchased as gifts may have region restrictions. Please see the gifts section for more information.
2023-10-17 07:30:13

Can a cloud hold a person?
Clouds can hold no weight at all. They are not a coherent material, but consist mostly of air, with tiny droplets of water (or ice crystals) suspended in it. You may have experienced fog. That's a cloud that's low enough that you're inside it when you're standing on the ground.
2023-09-04 04:08:41

Is it true that every alternate key is a unique key?
The remaining candidate keys are called unique keys because they can uniquely identify a record in a relation. Unique keys can consist of multiple columns. Unique keys are also called alternate keys. Unique keys are an alternative to the primary key of the relation.
2023-03-11 00:15:12

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