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Leer Challenge: Creating After Trigger | Some Additional Topics
Advanced Techniques in SQL
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Cursusinhoud

Advanced Techniques in SQL

Advanced Techniques in SQL

1. ACID
2. Query optimization.Indexes
3. Some Additional Topics

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Challenge: Creating After Trigger

Taak

Swipe to start coding

Now we will create a trigger to execute after updating the balance column of the BankAccounts table.
When triggered, it will invoke the function after_update_balance(), which logs the account number and the new balance into the UserLogs table, providing a record of balance modifications. The key idea is that we don't have to manually fill in the logs table - it will be done automatically by the trigger.

Note

Pay attention that triggers created for UPDATE operations can be designed to work only for update of the particular column. We can use the following statement to achive this:
CREATE TRIGGER trigger_name AFTER UPDATE OF col_name ON table_name.

Your task is to:

  • Create the after_update_balance() function. It should return a trigger as its result and perform the necessary action, which is updating logs.
  • Create an AFTER UPDATE trigger on the bankaccounts table. This trigger should use the designed function by executing it on each row of the update statement.

Oplossing

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Was alles duidelijk?

Hoe kunnen we het verbeteren?

Bedankt voor je feedback!

Sectie 3. Hoofdstuk 2
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book
Challenge: Creating After Trigger

Taak

Swipe to start coding

Now we will create a trigger to execute after updating the balance column of the BankAccounts table.
When triggered, it will invoke the function after_update_balance(), which logs the account number and the new balance into the UserLogs table, providing a record of balance modifications. The key idea is that we don't have to manually fill in the logs table - it will be done automatically by the trigger.

Note

Pay attention that triggers created for UPDATE operations can be designed to work only for update of the particular column. We can use the following statement to achive this:
CREATE TRIGGER trigger_name AFTER UPDATE OF col_name ON table_name.

Your task is to:

  • Create the after_update_balance() function. It should return a trigger as its result and perform the necessary action, which is updating logs.
  • Create an AFTER UPDATE trigger on the bankaccounts table. This trigger should use the designed function by executing it on each row of the update statement.

Oplossing

Switch to desktopSchakel over naar desktop voor praktijkervaringGa verder vanaf waar je bent met een van de onderstaande opties
Was alles duidelijk?

Hoe kunnen we het verbeteren?

Bedankt voor je feedback!

Sectie 3. Hoofdstuk 2
Switch to desktopSchakel over naar desktop voor praktijkervaringGa verder vanaf waar je bent met een van de onderstaande opties
Onze excuses dat er iets mis is gegaan. Wat is er gebeurd?
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