xact_abort & xact_state

xact_abort

Specifies whether SQL Server automatically rolls back the current transaction when a Transact-SQL statement raises a run-time error.

决定当有错误的时候 要不要roll back

The THROW statement honors SET XACT_ABORT. RAISERROR does not. New applications should use THROW instead of RAISERROR.
throw的可以用，raiserror 用不了

SET XACT_ABORT { ON | OFF }

---

When SET XACT_ABORT is ON, if a Transact-SQL statement raises a run-time error, the entire transaction is terminated and rolled back.

When SET XACT_ABORT is OFF, in some cases only the Transact-SQL statement that raised the error is rolled back and the transaction continues processing. Depending upon the severity of the error, the entire transaction may be rolled back even when SET XACT_ABORT is OFF. OFF is the default setting in a T-SQL statement, while ON is the default setting in a trigger.

Compile errors, such as syntax errors, are not affected by SET XACT_ABORT.

• 如果设置开，当遇到error时候，就roll back
• 如果设置关，在有些情况下， 错误的statement 会roll back，并且继续执行下面的语句
  根据severity 决定， 如果SET XACT_ABORT 是off，整个语句都要可能会roll back

link

XACT_ABORT must be set ON for data modification statements in an implicit or explicit transaction against most OLE DB providers, including SQL Server. The only case where this option is not required is if the provider supports nested transactions.

---

XACT_STATE

USE AdventureWorks2012;  
GO  
  
-- SET XACT_ABORT ON will render the transaction uncommittable  
-- when the constraint violation occurs.  
SET XACT_ABORT ON;  
  
BEGIN TRY  
    BEGIN TRANSACTION;  
        -- A FOREIGN KEY constraint exists on this table. This   
        -- statement will generate a constraint violation error.  
        DELETE FROM Production.Product  
            WHERE ProductID = 980;  
  
    -- If the delete operation succeeds, commit the transaction. The CATCH  
    -- block will not execute.  
    COMMIT TRANSACTION;  
END TRY  
BEGIN CATCH  
    -- Test XACT_STATE for 0, 1, or -1.  
    -- If 1, the transaction is committable.  
    -- If -1, the transaction is uncommittable and should   
    --     be rolled back.  
    -- XACT_STATE = 0 means there is no transaction and  
    --     a commit or rollback operation would generate an error.  
  
    -- Test whether the transaction is uncommittable.  
    IF (XACT_STATE()) = -1  
    BEGIN  
        PRINT 'The transaction is in an uncommittable state.' +  
              ' Rolling back transaction.'  
        ROLLBACK TRANSACTION;  
    END;  
  
    -- Test whether the transaction is active and valid.  
    IF (XACT_STATE()) = 1  
    BEGIN  
        PRINT 'The transaction is committable.' +   
              ' Committing transaction.'  
        COMMIT TRANSACTION;     
    END;  
END CATCH;  
GO  

https://docs.microsoft.com/en-us/sql/t-sql/functions/xact-state-transact-sql?view=sql-server-ver15