Answer:
Relational query language is the language that is used in the queries of the relational databases that has rows and columns in table. The user or client presents a request for gaining the information from the database. The relationships in the database are defined in numerous ways which creates the query.
This language can be procedural form or non-procedural form.The operations performed by this language are communication with the relational database, analyzing the relationships between the entities of database,splitting the request from client and then execution of that request is done by database management system(DBMS), etc.
Answer:
z = a.c' + a.b.d' + b.c'.d'
Explanation:
The truth table for this question is provided in the attachment to this question.
N.B - a' = not a!
The rows with output of 1 come from the following relations: 01 > 00, 10 > 00, 10 > 01, 11 > 00, 11 > 01, 11 > 10
This means that the Boolean expression is a sum of all the rows with output of 1.
z = a'bc'd' + ab'c'd' + ab'c'd + abc'd' + abc'd + abcd'
On simplification,
z = bc'd' + ab'c' + ac'd' + ac'd + abc' + abd'
z = ac' + abd' + bc'd'
Hope this helps!
A correlation is a consistent relationship between two or more variables. It relates to our tendency to draw causation from mere correlation.
Answer:
A closed port that can not receive request from authorized users.
Explanation:
Networks comprises of end devices, routing and switching devices, servers, technical control devices etc. The communication and interconnection of these devices makes up a secure and resourceful network.
Attackers can exploit loopholes in networks to steal information. The attackers uses the SYN scanning or cracking technique to implement the DOS or denial of service attack.
DOS is used to flood ports on a server in a network, preventing authorized user access, as they steal information to avoid detection.
