D426 Preview Quiz and Correct Answers
What is data?
numeric, textual, visual, or audio information that describes real-world systems. Data is collected
and processed to aid in a variety of tasks, such as forecasting weather, analyzing financial
investments, and tracking the global spread of pandemics.
What is a database?
a collection of data in a structured format. In principle, databases can be stored on paper or even
clay tablets. In practice, however, modern databases are invariably stored on computers. The
database structure ensures that similar data is stored in a standardized manner
What is a DBMS?
software that reads and writes data in a database. Database systems ensure data is secure,
internally consistent, and available at all times. These functions are challenging for large
databases with many users, so database systems are complex.
What is a transaction?
a group of queries that must be either completed or rejected as a whole. Execution of some, but
not all, queries results in inconsistent or incorrect data.
When processing a transaction, what must happen?
Ensure transactions are processed completely or not at all, Prevent conflicts between concurrent
transactions and Ensure transaction results are never lost (backed up)
What is a query processor?
Creates a plan to modify the database or retrieve data, and returns query results to the
application. Performs query optimization to ensure the most efficient instructions are executed
on the data.
What is data?
numeric, textual, visual, or audio information that describes real-world systems. Data is collected
and processed to aid in a variety of tasks, such as forecasting weather, analyzing financial
investments, and tracking the global spread of pandemics.
What is a database?
a collection of data in a structured format. In principle, databases can be stored on paper or even
clay tablets. In practice, however, modern databases are invariably stored on computers. The
database structure ensures that similar data is stored in a standardized manner
What is a DBMS?
software that reads and writes data in a database. Database systems ensure data is secure,
internally consistent, and available at all times. These functions are challenging for large
databases with many users, so database systems are complex.
What is a transaction?
a group of queries that must be either completed or rejected as a whole. Execution of some, but
not all, queries results in inconsistent or incorrect data.
When processing a transaction, what must happen?
Ensure transactions are processed completely or not at all, Prevent conflicts between concurrent
transactions and Ensure transaction results are never lost (backed up)
What is a query processor?
Creates a plan to modify the database or retrieve data, and returns query results to the
application. Performs query optimization to ensure the most efficient instructions are executed
on the data.
