Creating a Trigger and Throwing an Error

If the DOS Authority fails, the original operation also fails. INSTEAD OF triggers replace the call setup operation. In these scenarios, the INSERT , UPDATE , or DELETE functions are never executed, but instead the contents of most triggers are executed.

Can a trigger raise an error?

The first rule says that triggers are usually part of the calling transaction (the transaction that executes them). The second strange law of trading is that when a trade closesvaetsya in the trigger, the base also issues a stop error. An example of this rule is executing a COMMIT or possibly a ROLLBACK within a trigger.

I’m trying to help you create code that again includes two separate columns: months, year, and year. So I want to take advantage of this whether the numbers already entered are already there or not. If they succeed, make a mistake, then stop the transaction. Otherwise, I want to continue against each other and put new information into the table. I know I’m close to getting this job, but I can’t get RAISERROR when you want to shoot. I’m pretty sure it has to do with the fact that I’m new enough to this that I’m missing a small detail. i

Right now I’m taking 2+ months as variables and basically creating a third variable to invest in to instantly convert the other two to the correct datetime format. I have to use the datediff function to see if this person does it. Still unsuccessful. I always start the party, even if the card meeting is old.

ISP  USE AdventureWorks2012
WALK

CREATE A BadCreditCardDate TRIGGER
Sales software. Credit card
INSTEAD OF INSERT
AS? OR WHAT
to begin
DECLARE @ExpMonth tinyint,
        @ExpYearsmallint,
        @ExpMonthYear date-time

CHOOSE @ExpMonth=ExpMonth,
        @ExpYear=ExpYear,
        @ExpMonthYear is equal to @ExpYear + '-' + @ExpMonth + '-00'
BY DEPLOYED
    IF
    DATEDIFF(MONTH,@ExpMonthYear,GETDATE()) < 0
    TO BEGIN
        RAISERROR('The credit card you entered has expired.',10,1)
        CANCELING A TRANSACTION
    END

DIFFERENT
to begin
    INSERT INTO CreditCard(CardType, CardNumber, ExpMonth, ExpYear, ModifiedDate)
    Select CardType, CardNumber, ExpMonth, ExpYear, ModifiedDate FROM inserted
END
end

The goal of this article is to provide a simple and easy-to-use error handling mechanism that provides context. This article is fully compatible with anyone with SQL Server.
2012 and 2014

  • The original rule is that triggers are actually part of the calling transfer (the transaction that initiated them). Yes, the element is True and means that you initially increment both @@trancount values
    and so xact_state() is "1". If so, we integrate into the COMMIT or ROLLBACK trigger,their unique values ​​only change to "0" after these instructions are executed. Secondly
  • An unfamiliar rule is that if a trade ends on a trigger, the catalog issues a stop error. The position at which this rule is executed is COMMIT or ROLLBACK in the trigger. Solution
  • This uses the second rule in the rollback trigger and generates an error. The following code demonstrates this packaging mechanism:

    How do you handle trigger errors in SQL?

    To test each trigger, we run a T-SQL UPDATE statement to set the OrderStatus value for the first and most important row in the table to Approved (pkID is 1). After the T-SQL UPDATE command word, we run a T-SQL SELECT query to make sure the cast command is executing correctly.

    This works well as long as RAISERROR is often not the last statement in a trigger. If we have instructions after RAISERROR,
    They are executed as shown in the following code:

    This solution applies to SQL Server 2012 and later. The THROW statement improves error handling around triggers. It resets the instructions and also throws an error message. The following standard demonstrates this mechanism:

    As I explained earlier
    previous article
    , the introduction of THROW, a statement type, was a revolutionary step in SQL Server 2012 error handling.Z proves it, this duration with triggers.

    Why do I get errors when retrying a SQL Server transaction?

    If a great error is returned, it "looks like" a SQL Server transaction that is being rolled back and rolled back. This poses a real problem because although this transaction will necessarily be redone, NO other specific call records are inserted into the web SQL table. I can only assume that some kind of telephone system will work.

    Â - Get and print the morale at the beginning of each of our triggers

    What are triggertriggers in SQL?

    Triggers are nothing, although they are logically stored processes that can run automatically before an insert, update, or delete on a table, or after an insert, update, or delete. Updates or deletions often occur on a table.

    PRINT
    'When the trigger fires, @@trancount value is real ("
    + @trancount + ' ).';

    PRINT
    'If the trigger does indeed return an XACT_STATE() value ('
    + @XACT_STATE + ' ).';

    PRINT
    'After executing the COMMIT @@trancount statement, the value ('
    + @trancount + ' ).Run ';

    Which SQL statement is used to manually generate an error?

    Introducing the SQL Server RAISEERROR statement. The RAISERROR statement allows you to generate your company's own error messages and send those product messages back to the application using the same format as a functional error or warning message generated while running the SQL Server Database engine.

    Print
    'After the COMMIT statement, the return value of XACT_STATE() is ('
    + @XACT_STATE + ' ).';

    Errors generated by RAISERROR work in the same way as errors thrown by the database engine code. Community functions ERROR_STATE and @@ERROR. When RAISERROR with severity 11 or higher is fired inside a TRY, it transfers control to its associated CATCH block. Error occurs when calling RAISERROR at runtime:

    With a severity of 10 or less in a boulder with a very ATTEMPT.

    If the severity is 20 or higher, the connection to the data source will be terminated.

    If you are in a Triggerfast context, errors will appear on the stack and roll back the transaction for us.

    When it comes to error handling in SQL Server, no rule is unique without exceptions. Errors that a human self initiates with RAISERROR don't start falling onto the stack, even in the context of a trigger

    There is another direction in which the trigger can complete these packets. This happens if @@trancount is 0 when the trigger ends. A trigger is always executed from the point of view of a transaction, because even the actual event of no transaction with multiple trigger statements is definitely part of that transaction.
    Document


    1> Create employee table (
    2>IDinteger,
    3> name nvarchar(10),
    4>Salaryint )
    5> GO
    1>
    2> Create table task (
    3>IDinteger,
    4> denote nvarchar(10),
    5>average salaryint)
    6> GO
    1>
    2>
    3> Insert employee numbers (ID, name, salary) (1, 'Jason', 1234)
    4> GO

    (1 line(s) affected)
    1> Insert employee values ​​(id, name, salary) (2, 'Robert', 4321)
    2> GO

    (1 line concerns)
    1> insert employee increments (id, name, salary) (3, 'Celia', 5432)
    2> GO

    (1 row affected)
    1> Insert employee values ​​(id, name, salary) (4, 'Linda', 3456)
    2> GO

    (1 episode affected)
    1> Insert employee prices (id, name, salary) (5, 'David', 7654)
    2> GO

    (1 line(s) affected)
    1> insert into candidate values ​​(id, name, salary) (6, 'James', 4567)
    2> GO

    (1 episode affected)
    1> Insert employee standards (id, name, salary) (7, 'Alison', 8744)
    2> GO

    (1 row affected)
    1> Insert employee values ​​(id, name, salary) (8, 'Chris', 9875)
    2> GO

    (1 line concerns)
    1> Paste in employee reviews (ID, name, salary) (9, 'Mary', 2345)
    2> GO

    (1 row affected)
    1>
    2> insert into Job(ID, Position, Average salary) Values(1,'Pdeveloper',3000)
    3> GO

    (1 episode affected)
    1> insert into Job(ID, Position, Average Salary) Values(2,'Tester', 4000)
    2> GO

    (1 line concerns)
    1> insert into Job(ID, Position, Average salary) Values(3,'Designer', 5000)
    2> GO

    (1 line(s) affected)
    1> hired (id, position, average salary) values ​​(4,'programmer', 6000)
    2> GO

    (1 row affected)
    1>
    2>
    3> select 3 . employee;
    4> GO
    Wage
    -------------------------------
    1 Jason 1234
    2Robert 4321
    couple Celia 5432
    8 Linda 3456
    all five Davids 7654
    Stage 6 James 4567
    new Alison 8744