exams and notes

A salesperson is authorized to sell many products and a product can be sold by many salespersons. Which kind of binary relationship does this scenario describe? - Many-to-many Which kind of relationship is displayed in this entity-relationship diagram? - Many-to-many unary Which two examples are attributes? Choose 2 answers - AN Employee number, and meeting code Which delete rule sets column values in a child table to a missing value when the matching data is deleted from the parent table?...

Syntax for updating a specific column in a specific row - UPDATE <table> SET <atrribute> = <value> WHERE <primary key> = <value>; Syntax for deleting a row - DELETE FROM <TableName> WHERE <PrimaryKey> = <#>; Syntax for creating a view - CREATE VIEW <name> AS SELECT <columnname> CONCAT (<attribute>, ' ', <attribute>) AS <newname>, <attributes> FROM <tablename> Syntax to create an Index - CREATE IN...

Access plan -A set of instructions generated at application compilation time that is created and managed by a DBMS. The access plan predetermines how an application's query will access the database at run time. Alias -An alternative name for a column or table in a SQL statement. ALTER TABLE -The SQL command used to make changes to table structure. When the command is followed by a keyword (ADD or MODIFY), it adds a column or changes column characteristics. AREA -In DB2, a named section of...

A salesperson is authorized to sell many products and a product can be sold by many salespersons. Which kind of binary relationship does this scenario describe? One-to-one One-to-many Many-to-many One-to-one binary - Many-to-many Which two examples are attributes? Choose 2 answers A person attending a meeting An employee number A sales meeting A meeting code - An employee number A meeting code Which delete rule sets column values in a child table to a missing value when the matching...

DML - IUDS, CR insert, update, delete, select commit, rollback INSERT - add new rows UPDATE - modify data of existing rows DELETE - delete some/all records from database can be rolled back COMMIT - permanently saves ROLLBACK - undo changes SELECT - data retrieval WHERE - limits rows returned used before group by ORDER BY - OC sorts columns

An entity is said to be X -dependent if it can exist in the database only when it is associated with another related entity occurrence. - existence A table that has all key attributes defined has no repeating groups and all its attributes are dependent on the primary key is said to be in X. - 1nf A determinant is any attribute whose value determines other values within a column. - F X is a process that is used for changing attributes to entities. - Normalization Any attribute whose value d...

First Normal Form - - when all non-key columns depend on the primary key - a table with a primary key is in first normal form - a table with no duplicate rows is in first normal form Second Normal Form - - when all non-key columns depend on the whole primary key - cannot depend on part of a composite primary key - a table with a simple primary key is automatically in second normal form A table with a simple primary key must be in what normal form? - - second normal form or higher Third N...

An inequality condition is also known as a natural join and an equality condition is also called a theta join. - False When using a(n) _____ join, only rows that meet the given criteria are returned. - inner The statement SELECT * FROM T1, T2 produces a(n) _____ join. - cross A(n) _____ join will select only the rows with matching values in the common attribute(s). - natural If a designer wishes to create an inner join, but the two tables do not have a commonly named attribute, he can use...

An alias is especially useful when a table must be joined to itself in a(n) ___________________ query. - recursive The ___________ condition is generally composed of an equality comparison between the foreign key and the primary key of related tables. - join A database language enables the user to create database and table structures to perform basic data management chores. - TRUE ______________________ is the process the DBMS uses to verify that only registered users access the database....

AREA - In DB2, a named section of permanent storage space that is reserved to store the database. associative entity - See composite entity. bridge entity - See composite entity. candidate key - A minimal superkey; that is, a key that does not contain a subset of attributes that is itself a superkey. See key. closure - A property of relational operators that permits the use of relational algebra operators on existing tables (relations) to produce new relations. composite entity - An enti...