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Unmasking CXPACKET and CXCONSUMER in SQL Server: What Your Execution Plan Isn’t Telling You

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State Transition Constraints

About two decades ago, I introduced the concept of transition constraints to show Data Validation in a database is a lot more complex than seeing if a string parameter really is an integer. In October of 2008, I did an article called Constraint Yourself! on how to use DDL constraints to assure data integrity. One of the topics in that piece was a look at state transition constraints via an auxiliary table.

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In the US, this is the Independence Day weekend. I had a few spare vacation days, so I tacked one on, making this a four day weekend. My plans are simple. Prep for my family coming over on the 5th for a celebration of the 4th (Ha!). Work on my query tuning book (gotta make […]

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Hello, Grant again as Steve is on sabbatical. My evenings and weekends are currently being used to update my SQL Server query performance book for 2025. I really enjoy it because writing the book forces me to structure my learning on SQL Server 2025, not just hit it in some slipshod manner. Plus, I've got […]

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Hey all! It's me, Grant. For those who don't me, Grant Fritchey. I work with Steve Jones, the person normally talking to you here. Yes, Redgate actually employs me, and continues to. I don't know why either. Anyway, Steve is off for a few weeks on his sabbatical. More power to him and I hope […]

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Question of the Day

Changing the Schema

I set up a few users on my SQL Server 2022 instance.

CREATE LOGIN User1 WITH PASSWORD = 'Demo12#1'
CREATE USER User1 FOR LOGIN User1
GO
CREATE LOGIN User2 WITH PASSWORD = 'Demo12#2'
CREATE USER User2 FOR LOGIN User2
GO
CREATE LOGIN User3 WITH PASSWORD = 'Demo12#3'
CREATE USER User3 FOR LOGIN User3
GO
I then created a schema that one of them owned. Under this schema, I added a table with some data.
CREATE SCHEMA MySchema AUTHORIZATION User1
GO
CREATE TABLE Myschema.MyTable(myid INT)
GO
INSERT MySchema.MyTable
(
    myid
)
VALUES
(1), (2), (3)
GO
SELECT * FROM MySchema.MyTable
GO
I granted rights and verified that User2 could access this table.
GRANT SELECT ON Myschema.MyTable TO User2
GO
SETUSER 'USER2'
GO
SELECT * FROM MySchema.MyTable
GO
This worked. Now, I move this schema to a new user.
ALTER AUTHORIZATION ON SCHEMA::Myschema TO User3;
GO
What happens with this code?
SETUSER 'USER2'
GO
SELECT * FROM MySchema.MyTable
GO

See possible answers