Data Management
Foundations Study Guide
C175 Exam Questions
and Complete Solutions
Graded A+
Denning [Date] [Course title]
, Why databases? - Answer: ·Helps organizations use data / information as a resource to make decisions
File based structure (Prior to BDMS) - Answer: o Attempt to computerize old manual filing system
o Was easy to retrieve small amounts of information from
o As data grew, it became difficult to locate and retrieve information
o Retrieval speed depended on file structure and how data was organized within the structure
File types that utilized file based structure - Answer: Flat files, heap files, Index files, hashed files
Flat files - Answer: no internal hierarchy and data is unstructured
Heap files - Answer: unsorted set of records uniquely identified by record ID
-allows heap files to be inserted or deleted using ID
index files - Answer: · File that stores a list of Look Up Field values from data file that includes the
location (address) in the data file of the corresponding record
· Smaller than the entire record, usually fits in main memory for quick look up
· Lists keywords and phrases that are in a particular file
· Becomes a pointer to the location in the file where the information can be found when stored with
keywords and phrases
hashed files - Answer: · Uses hash functions to decide where records should be placed on a disk
· Allows for faster data look up without the use of an index file
data - Answer: raw facts not processed to reveal meaning. Requires transformation to better
understand.
information - Answer: o Produced by Processing Raw Data to reveal its meaning
o Key to good decision making and business survival is accurate, relevant, and timely information
Foundations Study Guide
C175 Exam Questions
and Complete Solutions
Graded A+
Denning [Date] [Course title]
, Why databases? - Answer: ·Helps organizations use data / information as a resource to make decisions
File based structure (Prior to BDMS) - Answer: o Attempt to computerize old manual filing system
o Was easy to retrieve small amounts of information from
o As data grew, it became difficult to locate and retrieve information
o Retrieval speed depended on file structure and how data was organized within the structure
File types that utilized file based structure - Answer: Flat files, heap files, Index files, hashed files
Flat files - Answer: no internal hierarchy and data is unstructured
Heap files - Answer: unsorted set of records uniquely identified by record ID
-allows heap files to be inserted or deleted using ID
index files - Answer: · File that stores a list of Look Up Field values from data file that includes the
location (address) in the data file of the corresponding record
· Smaller than the entire record, usually fits in main memory for quick look up
· Lists keywords and phrases that are in a particular file
· Becomes a pointer to the location in the file where the information can be found when stored with
keywords and phrases
hashed files - Answer: · Uses hash functions to decide where records should be placed on a disk
· Allows for faster data look up without the use of an index file
data - Answer: raw facts not processed to reveal meaning. Requires transformation to better
understand.
information - Answer: o Produced by Processing Raw Data to reveal its meaning
o Key to good decision making and business survival is accurate, relevant, and timely information
