Database and OLTP — Learn free

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Questions 1–10 of 10

1. What is a database, in the simplest definition?
Question 1A. A dimensional model of business factsB. A medium to store structured dataC. A tool for scraping websitesD. A network of servers rented from a cloud vendorE. A report produced for decision makers
2. Why can a database not be linked to any one data modelling solution?
Question 2A. Because databases only support NoSQL modelsB. Because OLTP, data warehouses, data marts and OLAP all use databases as the medium to store their data setsC. Because databases cannot store relationsD. Because data models are stored on tape drivesE. Because databases predate data modelling
3. What does OLTP (Online Transaction Processing) do?
Question 3A. Stores pre-aggregated cubes for analysisB. Stores business transactions in real time with insert, update and delete capability and the ACID featureC. Archives historical data on tape drivesD. Virtualises data from multiple sourcesE. Extracts data from web pages
4. Under which term do data warehouses and data marts normally fall?
Question 4A. OLTP (Online Transactional Processing)B. OLAP (Online Analytical Processing)C. NoSQLD. Big DataE. Data virtualization
5. Which statement about Big Data and Data Lakes in relation to OLTP and OLAP is correct?
Question 5A. They are firmly classified as OLTPB. They are firmly classified as OLAPC. The data world has yet to tag them as OLTP or OLAP, but they are certainly not meant for OLTPD. They replace both OLTP and OLAPE. They are classified as RDBMS
6. Why are databases called RDBMS (relational database management systems)?
Question 6A. Because they store data on related serversB. Because data in tables can be joined with each other using relationsC. Because they are related to a data warehouseD. Because every table has a relation to a tape backupE. Because they relate to real-time reporting
7. What is the purpose of the normalisation concept in the OLTP world?
Question 7A. To speed up reporting queriesB. To make sure there is no duplication of dataC. To pre-aggregate KPIsD. To encrypt sensitive columnsE. To convert NoSQL data into tables
8. In Third Normal Form (3NF), data modellers keep breaking tables until what condition is met?
Question 8A. Every table has fewer than ten columnsB. All non-key columns are dependent on key columnsC. All tables fit on a single tape driveD. Every table has a foreign key to a fact tableE. No table contains more than one row per customer
9. Before the 1990s, why did organisations offload OLTP data to tape drives, and what challenge did this bring?
Question 9A. Storage and processing were expensive; it created a challenge in decision-making on historical dataB. Tape was faster than disk; it created a challenge of duplicate recordsC. Regulators required it; it created a challenge of data sovereigntyD. Databases could not store text; it created a challenge of encodingE. Networks were unreliable; it created a challenge of table locking
10. Why did the normalised (3NF) extraction copy of OLTP become a bottleneck for decision-support queries?
Question 10A. Because it could not store more than a few KPIsB. Because queries had to join tens or hundreds of tables, slowing a single query from minutes to 10–20 hoursC. Because table locking prevented any readsD. Because it was stored on tapeE. Because it lacked the ACID feature