File structures fundations

Question 1

File

Answer 1

A collection of related records, usually stored in a structured format.

Question 2

Serial file organization

Answer 2

Records are stored one after the other, in the order they are entered.

Question 3

Sequential file organization

Answer 3

Records are stored in a sorted order based on a key field.

Question 4

Indexed file organization

Answer 4

An index is used to enable fast access to records based on key values.

Question 5

Hashed file organization

Answer 5

A hash function determines the storage location of a record.

Question 6

Archives

Answer 6

Files or sets of files intended for long-term storage of records.

Question 7

Records

Answer 7

Structured collections of related fields, similar to rows in a database table.

Question 8

Field

Answer 8

The smallest unit of data, representing a single attribute or piece of information.

Question 9

Blocks

Answer 9

The smallest unit of data transfer between secondary storage and memory.

Question 10

Expanded record

Answer 10

A logical record that spans more than one block.

Question 11

Blocking

Answer 11

The process of storing multiple logical records within a single block.

Question 12

Blocking Factor

Answer 12

The number of logical records that can fit into one block.

Question 13

Index

Answer 13

An auxiliary data structure that enables fast access to records using key values.

Question 14

Indexing key

Answer 14

The field whose value is used to build and search the index.

Question 15

Privileged key

Answer 15

A key field with a direct or optimized access mechanism.

Question 16

Alternative key

Answer 16

A secondary field used for querying that is not the primary index.

Question 17

Consecutive organization

Answer 17

Records are stored contiguously without gaps between them.

Question 18

Non-consecutive organization

Answer 18

Records can start at arbitrary locations; blocks may not contain complete records.

Question 19

Bucket

Answer 19

A logical grouping of one or more blocks for organizing records.

Question 20

Key

Answer 20

A field used to identify, access, or sort records.

Question 21

Bucket space

Answer 21

The physical storage space allocated to a bucket.

Question 22

Bucket extent

Answer 22

The average number of records that can fit into a bucket.

Question 23

Cell

Answer 23

A bucket smaller than a block, typically for compact storage.

Question 24

Vector

Answer 24

A fixed-size collection of elements with a shared interpretation.

Question 25

Repeating group

Answer 25

A set of fields that can repeat multiple times within a record.

Question 26

Volume of record

Answer 26

The total allocated space for a record, including unused space.

Question 27

Occupation of record

Answer 27

The portion of a record that contains actual (non-empty) data.

Question 28

Ideal record density

Answer 28

(Occupation of record ÷ Volume of record) × 100%.

Question 29

Pointer

Answer 29

A reference to the location of a record, field, or related structure.

Question 30

Minimum Occupation (space)

Answer 30

The threshold below which space can be reused (e.g., pctused).

Question 31

Maximum Occupation (extent)

Answer 31

The limit above which no new records are inserted.

Question 32

Control fields

Answer 32

Metadata or fields used to manage and interpret the structure of a record.

Question 33

Purpose of marks

Answer 33

Help interpret data correctly, support dynamic fields, and mark boundaries.

Question 34

Field coding

Answer 34

Technique to reduce record size using efficient data types.

Question 35

Numeric coding

Answer 35

Replacing character-based numbers with machine-efficient numeric types.

Question 36

Enumerated coding

Answer 36

Mapping string values to numbers for compact storage.

Question 37

Bitmask

Answer 37

A structure where each bit represents a binary condition or flag.

Question 38

Real density of a file

Answer 38

The ratio of useful data to total file volume.

Question 39

Occupation density of a non-consecutive file

Answer 39

Ratio of the number of records to total capacity.

Question 40

Process Relative Frequency

Answer 40

How often a process is used relative to all other processes on a file.

Question 41

Global cost

Answer 41

A process's cost weighted by its relative frequency of use.

Question 42

Actualization

Answer 42

Any modification or update made to the file.

Question 43

Retrieval

Answer 43

The process of accessing information from a file.

Question 44

Disk sequentiality

Answer 44

The degree to which file data is physically stored in a sequential manner.

Question 45

Real cost

Answer 45

Calculated as: global cost × (1 − hit ratio).

Question 46

Archive subprocess

Answer 46

File update involving writing new data to disk for long-term storage.

Question 47

Validation subprocess

Answer 47

Checks whether an operation is permitted.

Question 48

Integrity subprocess

Answer 48

Ensures structural relationships and constraints remain valid.

Question 49

Location subprocess

Answer 49

Verifies the correct location of data before modification.

Question 50

Selective Retrieval

Answer 50

Retrieving specific records that meet certain criteria.

Question 51

Univocal selection

Answer 51

Retrieving a unique record using a key that identifies a single entry.

Question 52

Non-univocal selection

Answer 52

Retrieving multiple records that match a shared key.

Question 53

Simple selection

Answer 53

Searching based on a condition involving a single field.

Question 54

Multikey selection

Answer 54

Using multiple fields and conditions to retrieve records.

Question 55

Full scan

Answer 55

Sequentially reading every record in the file.

Question 56

Bucket filtering

Answer 56

Using metadata about buckets to narrow down the search for a record.