D426 Ch 5: Data Storage

These flashcards cover key concepts and details about storage media, indexing, and database operations discussed in the lecture.

Reading one gigabyte takes about __.

one second.

Used to store petabytes (millions of gigabytes) of user data in the cloud.

Magnetic disk (HDD)

Working memory (RAM)

Most expensive type of storage per byte.

The three types of storage are:

RAM, flash memory (SDD), and magnetic disks (HDD).

Each track on a __ contains sectors that hold data.

magnetic disk

A storage controller is responsible for managing __ in computing.

data flow

Flash memory is divided into __.

pages and blocks

Storage can be organized into blocks of __ bytes.

4 kilobytes.

A __ is a collection of related data treated as a unit.

table.

The __ of an index can speed up data retrieval.

structure.

An index on the table sort __ helps in efficient searching.

column.

A compiled reservation list for flights includes __ among other fields.

Flight Number.

An index with one entry for each table __ is known as a dense index.

row.

A __ index may only include entries for certain blocks instead of every row.

sparse.

If a database table is partitioned, it is divided into __ for easier management.

sections.

CREATE INDEX is a command used to create an __ in a database.

index.

A primary index is based on the __ key of a table.

primary.

To drop an index, use the command __.

DROP INDEX.

A __ allows you to designate where data is stored in a database system.

tablespace.

Partitions can be created based on __ values for efficient queries.

range.

The command to create a table is __ TABLE.

CREATE.

In table structures, each row may contain __ of data.

columns.

Physical design focuses on how data is __ on storage media.

arranged.

A bitmap index stores information as __ of bits.

sequences.

The __ query is used to extract data from one or more tables in a database.

SELECT.

The __ column is where searching is typically most efficient.

sort.

SQL commands for data manipulation include SELECT, __, and DELETE.

INSERT.

An optimized index can greatly reduce the time it takes to retrieve __.

data.

In a sorted index, rows are ordered based on the __ of a specified column.

values.

Indexes can be created on multiple __ to enhance performance.

columns.

An index does not store actual data, but rather __ to the data.

pointers.

__ can be a crucial factor in determining the speed at which data is retrieved.

Indexing.

The __ statement is used to describe how SQL queries will be executed by the database system.

EXPLAIN.

In terms of memory, a computer's main memory is often referred to as __.

RAM.

Data stored in a cloud environment is often __ accessible anywhere.

remotely.

An __ index helps in faster data retrieval compared to a non-unique index.

efficient.

The command that specifies how to fetch a result set efficiently is __.

EXPLAIN.

To create durable data storage, systems can use __ during backup and recovery processes.

snapshots.

Inserting new rows may require checking for __ to maintain data integrity.

primary key constraints.

USE __ to select a specific database before performing any operations.

USE DATABASE.

Transforming data for analysis can rely heavily on __ structures.

pivot.

One characteristic of a bitmap index is its ability to quickly identify __ across multiple queries.

frequencies.

An average flight data entry includes columns for Flight Number, __, and Departure Time.

Airline Name.

A list of values that shows how many rows each column covers is known as a __.

Cardinality.

Different types of index structures may be used to optimize searches for __.

performance.

Database management relies on the principles of data storage and __.

retrieval.

Cloud services typically charge based on __ used by the data storage.

amount of space.

The __ class of storage solutions might include modern databases.

filesystem.