WGU D412 Latest Update with complete solutions Of
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RELATIONAL DATABASE CONCEPTS
Functional Dependency – Relationship where one attribute’s value determines another’s
Determinant – Attribute used to determine the value of another attribute
Candidate Key – Unique, minimal attribute(s) that identify every non-key attribute
Primary Key – Column(s) used to uniquely identify a row
Foreign Key – Non-unique key that references a primary key
SQL LANGUAGE CATEGORIES
DDL (Data Definition Language) – Defines & manages database structures (CREATE, DROP,
ALTER, TRUNCATE, RENAME)
DML (Data Manipulation Language) – Adds, deletes, modifies stored data
DCL (Data Control Language) – Manages users, permissions, access
TCL (Transaction Control Language) – COMMIT and ROLLBACK
DQL (Data Query Language) – Retrieves data
VIEWS & METADATA
Materialized View – Stored view; uses memory; updates when base data changes
Virtual View – Not stored; computed when accessed
Metadata – Data about data (tables, columns, data types)
Base Table – Table referenced in a view
DATABASE STORAGE & ACCESS
Table Scan – Reads table blocks directly
Index Scan – Reads index blocks to locate table data
Binary Search – Index search by repeatedly splitting in half
Tablespace – Maps tables to a single physical file
, DATABASE DESIGN
Logical Design – Defines tables, columns, keys (schema)
Physical Design – Defines storage, indexes, partitions
Entity Class – Blueprint describing entity structure
Normalization – Reduces redundancy; each determinant must be a candidate key
Denormalization – Combines tables to improve performance (adds redundancy)
NORMAL FORMS
1NF – One value per cell
2NF – No partial dependencies
3NF – No transitive dependencies
BCNF – Every determinant is a candidate key
INDEXES
Primary (Clustering) Index – Sparse, sorted column
Secondary Index – Dense, non-sorted column
Dense Index – Entry for every row
Sparse Index – Entry per block
B+ Tree – All values in leaf nodes
B-Tree – Values may appear in higher levels
Hash Index – Uses hash function & buckets
Bitmap Index – Grid of bits
Multi-Column Index – Composite index
PARTITIONING
Partition – Subset of table data
Horizontal Partition – Subset of rows
Vertical Partition – Subset of columns
Range Partition – VALUES LESS THAN
List Partition – VALUES IN
Questyions And Answers Guarantee An A+ Grade
RELATIONAL DATABASE CONCEPTS
Functional Dependency – Relationship where one attribute’s value determines another’s
Determinant – Attribute used to determine the value of another attribute
Candidate Key – Unique, minimal attribute(s) that identify every non-key attribute
Primary Key – Column(s) used to uniquely identify a row
Foreign Key – Non-unique key that references a primary key
SQL LANGUAGE CATEGORIES
DDL (Data Definition Language) – Defines & manages database structures (CREATE, DROP,
ALTER, TRUNCATE, RENAME)
DML (Data Manipulation Language) – Adds, deletes, modifies stored data
DCL (Data Control Language) – Manages users, permissions, access
TCL (Transaction Control Language) – COMMIT and ROLLBACK
DQL (Data Query Language) – Retrieves data
VIEWS & METADATA
Materialized View – Stored view; uses memory; updates when base data changes
Virtual View – Not stored; computed when accessed
Metadata – Data about data (tables, columns, data types)
Base Table – Table referenced in a view
DATABASE STORAGE & ACCESS
Table Scan – Reads table blocks directly
Index Scan – Reads index blocks to locate table data
Binary Search – Index search by repeatedly splitting in half
Tablespace – Maps tables to a single physical file
, DATABASE DESIGN
Logical Design – Defines tables, columns, keys (schema)
Physical Design – Defines storage, indexes, partitions
Entity Class – Blueprint describing entity structure
Normalization – Reduces redundancy; each determinant must be a candidate key
Denormalization – Combines tables to improve performance (adds redundancy)
NORMAL FORMS
1NF – One value per cell
2NF – No partial dependencies
3NF – No transitive dependencies
BCNF – Every determinant is a candidate key
INDEXES
Primary (Clustering) Index – Sparse, sorted column
Secondary Index – Dense, non-sorted column
Dense Index – Entry for every row
Sparse Index – Entry per block
B+ Tree – All values in leaf nodes
B-Tree – Values may appear in higher levels
Hash Index – Uses hash function & buckets
Bitmap Index – Grid of bits
Multi-Column Index – Composite index
PARTITIONING
Partition – Subset of table data
Horizontal Partition – Subset of rows
Vertical Partition – Subset of columns
Range Partition – VALUES LESS THAN
List Partition – VALUES IN
