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3 years ago

What is a foreign key and how does it provide referential integrity?

Computers and Technology

1 answer:

Step2247 [10]3 years ago

4 0

Answer:

By definition a foreign key of table A is a primary key of another table B, thereby establishing a link between them.

To provide referential integrity you can use these referential actions:

<u>Cascade:</u> If rows in table B are deleted, the matching foreign key columns in table A are deleted.

<u>Set Null:</u> If rows in table B are deleted, the matching foreign key columns in table A are set to null.

<u>Set Default:</u> If rows in table B are deleted, the matching foreign key columns in table A are set with the default value of the column.

<u>Restrict:</u> A value in table B cannot be deleted or updated while as it is referred to by a foreign key in table A.

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Security controls are measures taken to protect systems from attacks on the integrity, confidentiality, and availability of the

pychu [463]

Answer:

ADMINISTRATIVE CONTROL

Explanation:

If a potential employee is required to undergo a drug screening an Administrative Control is what will be conducted on the employee because

Administrative controls are training, procedure, policy that limit or prevent exposure of an individual to hazards. Examples of administrative controls include training, supervision, timing of work. Administrative controls are also changes in work procedures such as written safety policies, rules, supervision which is the reason the employee has to undergo drug screening using Administrative controls.

6 0

4 years ago

How do you think advances in processors affect corporations that discover the computers they purchased just a couple of years ag

lozanna [386]

Answer:

Increased processor speed and multi core technologies.

Explanation:

The development of processors over the years is overwhelmingly fast. The CPU use to be cumbersome, expensive and computational speed was moderate.

As it evolves, the CPU was minimized to give rise to microprocessors.

Microprocessors are very fast, running millions of processes on its core. The multiple core processors helped to increase the speed of these processors.

When there are more than one core in a processor (dual, quad or octal core), it processes data in parallel reducing the time of execution compared to a one core processor.

A company having computers with single core would need to upgrade to a new computer with multi core processor to promote speed in data processing.

3 0

3 years ago

You have heard that the Linux distribution your are going to install to run a new application runs best on a RISC architecture.

Artyom0805 [142]

Answer:

SPARC .

Explanation:

When the user has understood they're required to install the linux distribution to set up a specific program works better on such a RISC architecture. SPARC must therefore find the device from which it would work that following distribution for the Linux. It is a RISC and ISA that was previously designed through both Fujitsu and Sun.

6 0

3 years ago

Dani wants to create a web page to document her travel adventures. Which coding language should she use? HTML Java Python Text

FromTheMoon [43]

Answer:

<h2>I would recommend Python Programming language</h2>

Explanation:

The major reason i recommend python is that It has a ton of resources, and community support, such that it is practically impossible to get stuck while carrying out a project

Python is easy,and lets you build more functions with fewer lines of code.

More so, provides a stepping stone to learning other code and it is a very flexible language

3 0

3 years ago

A compound boolean expression created with the ___ operator is true only if all its connected expressions are true.

kiruha [24]

The answer to this is OR..I think..Hope i helped

4 0

3 years ago