Under what circumstances are composite primary keys appropriate?

1 answer:

8 0

A composite primary key<span> is a set of several primary </span>keys<span> that, together, uniquely identifies each record.</span>
Primary keys are used as identifiers of composite entities. In this case each primary key combination is allowed only once in the *:* relationship.
Other case where primary keys are used is as identifiers of weak entities, where the weak entity has a strong identifying relationship with the parent entity.

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What changes could you make so that a message, "User input deemed invalid." during designing a simple calculator program for you

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The most appropriate change in this situation would be to change the message "User input deemed invalid" to "You made a mistake, try again, you can".

<h3>What should we change to improve the children's experience?</h3>

To improve children's experience with this new calculator program, we must adapt all the features of the program for children's users. Therefore, the buttons, the messages and everything related to this program must be suitable for their motor and brain development.

Therefore, it is considered that the message "User input deemed invalid" is not suitable for children because they may not understand this message or misinterpret it and desist from using the new program.

So, the most appropriate message to replace the previous message would be:

"You made a mistake, try again, you can"

Because this message is suitable for the friendly language that children use in their daily lives and they would better understand the message without giving up using the new program or the calculator.

Learn more about programs in: brainly.com/question/13264074

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