What are two rules of relational database?
Two integrity of the relational database:
(1) Entity Integrity
(2) Referential Integrity
(1) Entity Integrity – Primary key attributes may not be null.
The primary key uniquely identifies an entity, so it cannot be null and it
must have a unique value.
(2) Referential Integrity – A foreign key may have a null value or it may have
a value that exists as a primary key value in another table it references.
Computer Science & Information Technology
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The process of taking data and making it unreadable is known as which of the following?
A. Encryption B. Decryption C. Signing D. Verifying
Computer Science & Information Technology
In the statement x= a+b * c+e * f+g which is the first operation that is performed when this C++ statement is executed?
A. a + b B. b * c C. e * f D. f + g
Computer Science & Information Technology