MC Using Cypher, how do you get a list of all movies Wilfried Lemahieu has liked, when he has given at least four stars? MATCH (b:User)-[I:LIKES]-(m:Movie)
WHERE b.name = "Wilfried Lemahieu"
AND l.stars >= 4
RETURN m correct SELECT (b:User)--m:Movie)
WHERE b.name = "Wilfried Lemahieu"
AND m.starts >= 4 incorrect MATCH (b:User)-[I:LIKES]-(m:Movie)
WHERE b.name = "Wilfried Lemahieu"
AND m.stars >=4
RETURN m incorrect MATCH (b:User)--(m:Movie)
WHERE b.name = "Wilfried Lemahieu"
AND l.stars >= 4
RETURN m incorrect
MC Which statement is CORRECT? Some relational constructs, such as the many-to-many relationship, are harder to express using graph databases. incorrect The fact that most NoSQL databases adopt an eventual consistency approach is due to the CAP theorem, which states that strong consistency cannot be obtained when availability and partitioning has to be ensured. correct Stabilization relates to the waiting time between the start-up of a NoSQL system and when the system becomes usable to receive user queries. incorrect Replicas in a distributed NoSQL environment relate to making periodic backups of the database to a second system. incorrect
MC Which of the following is not an example of a NoSQL database? Graph based databases. incorrect XML based databases. incorrect Document based databases. incorrect All three can be regarded as NoSQL databases. correct
MC Which of the following statements describes NoSQL databases best? NoSQL databases are not capable to deal with large datasets. incorrect NoSQL databases do not support joins. incorrect A NoSQL database offers no support for SQL. incorrect NoSQL databases are non-relational. correct
MC Using Cypher, how do you get a list of all movies Wilfried Lemahieu has liked, when he has given at least four stars? MATCH (b:User)-[I:LIKES]-(m:Movie)
WHERE b.name = "Wilfried Lemahieu"
AND m.stars >=4
RETURN m incorrect SELECT (b:User)--m:Movie)
WHERE b.name = "Wilfried Lemahieu"
AND m.starts >= 4 incorrect MATCH (b:User)--(m:Movie)
WHERE b.name = "Wilfried Lemahieu"
AND l.stars >= 4
RETURN m incorrect MATCH (b:User)-[I:LIKES]-(m:Movie)
WHERE b.name = "Wilfried Lemahieu"
AND l.stars >= 4
RETURN m correct
MC Which statement is CORRECT? NoSQL databases focus heavily on consistency. incorrect According to the dissemination protocol, each node sends out an "are you (still) there and part of my network?" request to all other members in a node's known network. incorrect Document stores are built on the same ideas as key-value and tuple based database systems. correct Due to the new No-SQL technologies, relational databases will become obsolete. incorrect
MC Which statement is NOT CORRECT? Graphs are mathematical structures consisting of nodes and edges. incorrect Graph databases work particularly well on tree-like structures. incorrect Edges in graphs can be uni- or bidirectional. incorrect Graph models are not capable to model many-to-many relationships. correct
MC Which statement is CORRECT? Replicas in a distributed NoSQL environment relate to making periodic backups of the database to a second system. incorrect Some relational constructs, such as the many-to-many relationship, are harder to express using graph databases. incorrect Stabilization relates to the waiting time between the start-up of a NoSQL system and when the system becomes usable to receive user queries. incorrect The fact that most NoSQL databases adopt an eventual consistency approach is due to the CAP theorem, which states that strong consistency cannot be obtained when availability and partitioning has to be ensured. correct
MC What does the following Cypher query express?
OPTIONAL MATCH (user;User)-[:FRIENDS_WITH]-(friend;User)
WHERE user.name = "Bart Baesens"
RETURN user, count(friend) AS NumberOfFriends Get the node for Bart Baesens and all his friends. incorrect This query will fail if Bart Baesens is FRIENDS_WITH himself. incorrect Get the node for Bart Baesens and a count of all his friends, but only if at least one FRIENDS_WITH relation exists. correct Get the node for Bart Baesens and a count of all his friends, even if no FRIENDS_WITH relation exists. incorrect
MC Which statement is NOT CORRECT? According to CAP, a DBMS can only achieve one of the following three properties: consistency, availability and partition tolerance. correct Vertical scaling can be achieved by, for example, increasing storage capacity. incorrect Column oriented databases are more efficient when aggregates need to be calculated over many or all rows in the dataset. incorrect NoSQL databases are non-relational. incorrect