Database Management Exam 1(Completely solved)
Database correct answers ORGANIZED collection of RELATED data
- can store information about entities, their attributes, and their relationships
Related (Tabular) correct answers organized in tables/relations/files
- tables have rows (records)
- tables have columns (fields or attributes)
- data is linked using common fields
- order of columns and rows in each table is not important
2 Cardinal Rules of Databases correct answers 1. a table describes one entity
2. databases only contain needed data
Primary key values must be correct answers UNIQUE
Relational Database correct answers collection of tables (relations) with relationships
implemented through common columns in 2 or more tables
qualifying column names correct answers Tablename.Columnname
Joining Tables correct answers putting categories together and cutting out extraneous
information
Natural Join correct answers joins records from each original table that are common to both
Outer Join correct answers joins records from each original table including records not common
to both
Integrity Constraint correct answers any rule that data must follow in a database
ex. can't enter a new child name from a new family without first entering their parent
Problems with using a non-DB approach to data management (spreadsheet) correct answers
redundancy, difficulty accessing related data, limited security, and limited size
Redundancy correct answers duplication of data or the storing of the same data in more than one
place
Entity Relationship Diagram (ERD) correct answers Visual representation of a database
-can have more than one relationship between 2 entities
Many to Many Relationship correct answers requires creation of a new table whose primary key
is the combination of the primary keys of the original tables
One to Many Relationship correct answers include the primary key of the "one" table as a
foreign key in the "many" table
Database correct answers ORGANIZED collection of RELATED data
- can store information about entities, their attributes, and their relationships
Related (Tabular) correct answers organized in tables/relations/files
- tables have rows (records)
- tables have columns (fields or attributes)
- data is linked using common fields
- order of columns and rows in each table is not important
2 Cardinal Rules of Databases correct answers 1. a table describes one entity
2. databases only contain needed data
Primary key values must be correct answers UNIQUE
Relational Database correct answers collection of tables (relations) with relationships
implemented through common columns in 2 or more tables
qualifying column names correct answers Tablename.Columnname
Joining Tables correct answers putting categories together and cutting out extraneous
information
Natural Join correct answers joins records from each original table that are common to both
Outer Join correct answers joins records from each original table including records not common
to both
Integrity Constraint correct answers any rule that data must follow in a database
ex. can't enter a new child name from a new family without first entering their parent
Problems with using a non-DB approach to data management (spreadsheet) correct answers
redundancy, difficulty accessing related data, limited security, and limited size
Redundancy correct answers duplication of data or the storing of the same data in more than one
place
Entity Relationship Diagram (ERD) correct answers Visual representation of a database
-can have more than one relationship between 2 entities
Many to Many Relationship correct answers requires creation of a new table whose primary key
is the combination of the primary keys of the original tables
One to Many Relationship correct answers include the primary key of the "one" table as a
foreign key in the "many" table
