WGU
Access Time - Correct Answer The time required to access the first byte in a read or write operation.
Aggregate - Correct Answer Computes functions over multiple table rows, such as SUM and COUNT.
ALTER - Correct Answer This statement adds, deletes, or modifies columns on an existing table.
ALTER TABLE - Correct Answer This statement adds, deletes, or modifies columns on an existing table.
Analog Data - Correct Answer Most common before computers. Audio was recorded as vibrations impressed on vinyl
disks.
Application Programming Language (API) - Correct Answer A library of procedures or classes that links a host
programming language to a database.
Architecture - Correct Answer Describes the internal components AND the relationships between components.
Artificial Key - Correct Answer A single-column primary key created by the database designer when no suitable
single-column or composite primary key exists.
Attribute - Correct Answer A descriptive property of an entity.
B-Tree - Correct Answer If an indexed value appears in a higher level, the value is not repeated at lower levels.
Instead, a pointer to the corresponding table block appears in the higher level along with the value.
B+Tree - Correct Answer All indexed values appear in the bottom level. Pointers to table blocks appear only in the
bottom level. Since some indexed values also appear in higher levels, values are occasionally repeated in the index.
Base Table - Correct Answer A table specified in the view query's FROM clause.
BETWEEN operator - Correct Answer This operator provides an alternative way to determine if a value is between
two other values.
Binary - Correct Answer Operator that has TWO operands.
Binary Search - Correct Answer The database repeatedly splits the index in two until it finds the entry containing the
search value.
Bitmap Index - Correct Answer What type of index am I?
This index is a grid of bits.
Block - Correct Answer This is what databases and file systems use as a uniform size when transferring data
between main memory and storage media.
Boyce-Codd Normal Form - Correct Answer What normal form am I?
A table is in this normal form if whenever column A depends on column B, then B is unique. Columns A and B may
be simple or composite.
Bucket - Correct Answer A block or group of blocks containing index entries.
Business Rules - Correct Answer Relational rules specific to a particular database AND application. Discovered
during database design.
, Candidate Key - Correct Answer A simple or composite column that is unique and minimal. Minimal meaning that all
columns are necessary for uniqueness.
CAP Theorem - Correct Answer States that a distributed database cannot simultaneously be Consistent, Available,
and Partition-tolerant. Only two can be guaranteed, but not all three properties.
Cardinality - Correct Answer Refers to the maximum number of times INSTANCES in one entity can be related to
INSTANCES in another entity.
CASCADE - Correct Answer Propagates primary key changes to foreign keys.
Catalog/Data Dictionary/Repository - Correct Answer A directory of tables, columns, indexes, and other database
objects.
Cell - Correct Answer A single column of a single row. In relational databases, each contains exactly one value.
Cluster Key - Correct Answer This is what table clusters have. It is a column that is available in all interleaved tables.
Column - Correct Answer Has a name and a data type.
Column Constraint - Correct Answer Appears after the column name and data type in a CREATE TABLE statement.
Govern values in a single column.
Column-oriented/Columnar Storage - Correct Answer Each block stores values for a single COLUMN only.
Composite Primary Key - Correct Answer Consists of multiple columns and are denoted with parentheses ().
Condition - Correct Answer An expression that evaluates to a logical value.
Connection - Correct Answer A link between tools and the query processor.
Constraint - Correct Answer A rule that governs allowable values in a database.
Constraints - Correct Answer Implemented rules that are enforced by the database system.
CREATE TABLE - Correct Answer Creates a new table by specifying the table and column names.
CROSS-JOIN - Correct Answer Combines two tables WITHOUT comparing columns.
CRUD - Correct Answer Acronym for actions that can be performed by a query.
Data - Correct Answer Numeric, textual, visual, or audio information that describes real-world systems. It is collected
and processed to aid in a variety of tasks.
Data Control Language (DCL) - Correct Answer What language am I?
Commands that CONTROL a database. Includes administering privileges and committing data.
Data Definition Language (DDL) - Correct Answer What language am I?
Allows a database administrator to DEFINE the database structure, schema, and subschema.
Data Independence - Correct Answer Allows database administrators to improve query performance by changing the
organization of data on storage devices, without affecting query results or changes to programs.
Data Lake - Correct Answer An analytic database of raw, unprocessed data copied from multiple data sources.
Data Manipulation Language (DML) - Correct Answer What language am I?
Allows users to access and modify the data to MAKE queries, and GENERATE reports. Interacting with the data.