Forum Discussion
Data Warehouse Alter Table add default value constraint
I have been trying to add a DEFAULT constraint to a COLUMN. I saw at least one 2023 post stating to check SQL surface area that, as it read says that the ALTER TABLE is not supported, I added a PRIMARY KEY CONSTRAINT using an ALTER TABLE... it just works and therefore the documentation may need some updates.
I have not found any sample or discussion on the use of ALTER TABLE to specify a DEFAULT value. Since the documentation is not current there may be a way... the samples of ALTER TABLE to add a DEFAULT CONSTRAINT works well in on-prem SQL-SERVER but not in Microsoft Fabric Data Warehouse.
Hope that someone have some news about this...
Hi esobrino default constraints are not supported currently as per the documenation here: Primary, foreign, and unique keys - Microsoft Fabric | Microsoft Learn
- SQL analytics endpoint and Warehouse don't support default constraints at this time.
There's no news when they will be public either.
The ALTER TABLE support in the T-SQL Surface Area documenation states "
- ALTER TABLE ADD/ALTER/DROP COLUMN
And as you've discovered, ALTER TABLE is supported when creating unique, primary key, and foreign key constraints.
T-SQL surface area - Microsoft Fabric | Microsoft Learn
I hope that helps
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3 Replies
Hi Team
Can you please let me know when the DEFAULT CONSTRAINTS will be added to Fabric Warehouse.
Thanks,
Keerthinath.C.M
Hi esobrino default constraints are not supported currently as per the documenation here: Primary, foreign, and unique keys - Microsoft Fabric | Microsoft Learn
- SQL analytics endpoint and Warehouse don't support default constraints at this time.
There's no news when they will be public either.
The ALTER TABLE support in the T-SQL Surface Area documenation states "
- ALTER TABLE ADD/ALTER/DROP COLUMN
And as you've discovered, ALTER TABLE is supported when creating unique, primary key, and foreign key constraints.
T-SQL surface area - Microsoft Fabric | Microsoft Learn
I hope that helps
-------------------------------------------------------
If my post has been useful, please consider
provising Kudos and/or accepting as the Solution
-------------------------------------------------------
-----------------------------------------------
"
"
Isn't this a pain. I would love to know if this is on the road map. I'd like to understand the mechanisms in place with columnar store and parquet that causes this to be a problem. I would think that maybe delta table/sql interpreter could be made to allow this. Anyone want to comment?
