Database
Systems
Final Exam
SQL -answeris a domain-specific programming language designed for managing and
communicating with data held in a relational database management system
SQL is used for: -answer-creating databases
-adding, modifying and deleting database structures
-inserting, deleting and modifying records in databases
-querying databases
Data Definition Language (DDL) -answerused to create and modify the structure of the
database
example: CREATE ALTER or DROP
Data Manipulation Language (DML) -answerused to insert, modify, delete and retrieve
data
example: INSERT INTO UPDATE or DELETE
, Data Retrieval Language (DRL) -answerused to query or retrieve data from a database
example: SELECT
Data Control Language (DCL) -answerused for data access control
Transaction Control Language -answerused for managing database transactions
Keywords -answerThese have a very specific meaning in the language. The statement
must have at least one. These often define the operation that is performed
Identifiers -answerThese refer to the names of the tables and columns that are called or
manipulated
Null Value -answeris a marker for data that has not been entered or is missing,
unknown, or inapplicable
Not Null Constraint -answeris only a column constraint and not a table constraint; if you
don't specify a _____, the column will accept null values by default
Unique Constraint -answerforces each value of a column or table to be unique
Check Constraint -answerallows for limiting a particular column based on a particular
value rules
These include:
minimum or maximum value
specified value
range of values
ALTER table -answerprovides the ability to:
-add/drop a column
-alter a column's data type
-rename a column
-rename a table
-add, alter or drop a column's default value or null ability constraint
-add, alter or drop column or table constraints such as primary key, foreign key, unique
and check constraint
Select Statement -answeris the basic building block of any data query request. It is
command that pulls specific data from a particular table within the database highlighted
Limit Statement -answerit limits the number of rows that are shown
Order By -answeris used to sort by data in a particular column or columns
Select Distinct -answereliminates duplicate values
Systems
Final Exam
SQL -answeris a domain-specific programming language designed for managing and
communicating with data held in a relational database management system
SQL is used for: -answer-creating databases
-adding, modifying and deleting database structures
-inserting, deleting and modifying records in databases
-querying databases
Data Definition Language (DDL) -answerused to create and modify the structure of the
database
example: CREATE ALTER or DROP
Data Manipulation Language (DML) -answerused to insert, modify, delete and retrieve
data
example: INSERT INTO UPDATE or DELETE
, Data Retrieval Language (DRL) -answerused to query or retrieve data from a database
example: SELECT
Data Control Language (DCL) -answerused for data access control
Transaction Control Language -answerused for managing database transactions
Keywords -answerThese have a very specific meaning in the language. The statement
must have at least one. These often define the operation that is performed
Identifiers -answerThese refer to the names of the tables and columns that are called or
manipulated
Null Value -answeris a marker for data that has not been entered or is missing,
unknown, or inapplicable
Not Null Constraint -answeris only a column constraint and not a table constraint; if you
don't specify a _____, the column will accept null values by default
Unique Constraint -answerforces each value of a column or table to be unique
Check Constraint -answerallows for limiting a particular column based on a particular
value rules
These include:
minimum or maximum value
specified value
range of values
ALTER table -answerprovides the ability to:
-add/drop a column
-alter a column's data type
-rename a column
-rename a table
-add, alter or drop a column's default value or null ability constraint
-add, alter or drop column or table constraints such as primary key, foreign key, unique
and check constraint
Select Statement -answeris the basic building block of any data query request. It is
command that pulls specific data from a particular table within the database highlighted
Limit Statement -answerit limits the number of rows that are shown
Order By -answeris used to sort by data in a particular column or columns
Select Distinct -answereliminates duplicate values
