من يساعدني مساعدة عاجلة جدا

أود المساعدة في حل بعض التمارين إذا كان بالإمكان

أو على الأقل إفهامي المطلوب

What is a transaction and why do they have to be defined by developers?

وهذا هو المطلوب الرجوع له في الكتاب أضعه بين قوسين

إذ طلب ان نعتمد عليه في الإجابة

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Miranda learned that even a good DBMS requires programming to handle some complex issue. In developing a system, developers should examine all of the business processes and identify transaction elements. Also, they have to be sure that UPDATE and DELETE procedure s can handle concurrency issues.

Also professional application handle errors gracefully, write data triggers or module code to automate basic processes and perform all needed calculations, write additional cursor-based code if needed to perform advanced calculations.

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