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maxonik [38]
3 years ago
9

Consider the relational schema below: Students(sid: integer, sname: string, major: string) Courses(cid: integer, cname: string,

hours: integer) Enrollment(sid: integer, cid: integer, grade: real) Write a relational algebra expression that satisfies this query? Find the distinct names of all students that take at least three courses and major in "Philosophy".
Computers and Technology
1 answer:
daser333 [38]3 years ago
7 0

Solution :

Here, we need to perform JOIN operation of the students and registration.

Use NATURAL JOIN operator \Join and so no need to specify Join condition.

Also we need to selection operator tp select only those course whose major in "philosophy".

Finally we projection operator π to project only distinct students name who took at least three courses.

$\pi [\sigma_{\text{student's nam}e} [ \sigma(\text{three courses}) \Join \text{"Philosophy"}]]$

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Is technology a legal discipline or law is a technological artifact.
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Answer:Technology law scholars have recently started to consider the theories of affordance and technological mediation, imported from the fields of psychology, human-computer interaction (HCI), and science and technology studies (STS). These theories have been used both as a means of explaining how the law has developed, and more recently in attempts to cast the law per se as an affordance. This exploratory paper summarises the two theories, before considering these applications from a critical perspective, noting certain deficiencies with respect to potential normative application and definitional clarity, respectively. It then posits that in applying them in the legal context we should seek to retain the relational user-artefact structure around which they were originally conceived, with the law cast as the user of the artefact, from which it seeks certain features or outcomes. This approach is effective for three reasons. Firstly, it acknowledges the power imbalance between law and architecture, where the former is manifestly subject to the decisions, made by designers, which mediate and transform the substance of the legal norms they instantiate in technological artefacts. Secondly, from an analytical perspective, it can help avoid some of the conceptual and definitional problems evident in the nascent legal literature on affordance. Lastly, approaching designers on their own terms can foster better critical evaluation of their activities during the design process, potentially leading to more effective ‘compliance by design’ where the course of the law’s mediation by technological artefacts can be better anticipated and guided by legislators, regulators, and legal practitioners.

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7 0
2 years ago
Beside homework, what products can you use for personal use? Identify three uses and briefly describe.
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Oksana_A [137]

Data visualization

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privilege escalation.

Explanation:

An access control can be defined as a security technique use for determining whether an individual has the minimum requirements or credentials to access or view resources on a computer by ensuring that they are who they claim to be.

Simply stated, access control is the process of verifying the identity of an individual or electronic device. Authentication work based on the principle (framework) of matching an incoming request from a user or electronic device to a set of uniquely defined credentials.

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Hence, an access control list (ACL) primarily is composed of a set of permissions and operations associated with a user account or new technology file system (NTFS) file such as full control, read only, write, read and execute and modify.

In this scenario, an attacker or hacker was able to obtain the logon credentials for a regular user on your network. Thus, the type of security threat which exists if this user account is used by the attacker or hacker to perform administrative functions is privilege escalation.

Privilege escalation can be defined as a network or security threat which involves the exploitation of a design flaw, bug or unsecured configuration settings in a software program (application), operating system (OS), computer system, etc., so as to have an unauthorized access and gain more permissions, elevated rights or privileges that are normally protected from a user account or software program.

Hence, when an attacker or malicious user such as a hacker gains an unauthorized access to the privileges of another user account beyond what is intended or entitled to a user, it is known as privilege escalation.

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