DACO study materials
DACO study resources

DACO key terms

DACO · Get comfortable with the vocabulary.

Data Governance

The exercise of authority and control over data assets through decision rights, policies, and accountability structures, ensuring data is managed as a valued organizational asset rather than an incidental byproduct.

Related: Data Stewardship, Data Ownership, Data Policy
Data Stewardship

The operational assignment of responsibility for a data domain's quality, definitions, and issue resolution to named individuals who act on behalf of the organization, distinct from legal or budgetary ownership.

Related: Data Governance, Data Custodian, Data Quality Dimensions
Data Ownership

Accountability assigned to a role for a specific data domain, including approving definitions, access decisions, and quality targets. Owners are answerable for outcomes; they typically delegate day-to-day execution to stewards.

Related: Data Stewardship, Data Custodian
Data Custodian

The role responsible for the technical safekeeping of data: storage, backup, access provisioning, and platform controls. Custodians execute the rules set by owners and stewards rather than deciding them.

Related: Data Ownership, Data Stewardship
Data Policy

A formal statement of principles and mandatory rules governing how data is acquired, used, protected, retained, and disposed of, providing the authority basis for standards and procedures that follow.

Related: Data Standard, Data Governance, Data Retention
Data Standard

A documented, mandatory rule specifying format, naming, allowed values, or encoding for a data element or process, translating policy intent into testable requirements that systems and staff can comply with.

Related: Data Policy, Data Dictionary, Reference Data
Data Maturity Model

A staged framework describing progressive capability levels, from ad hoc to optimized, used to assess an organization's data management practices and plan prioritized improvements with measurable milestones.

Related: Data Governance, Data Quality Dimensions
Conceptual Data Model

A technology-independent representation of business entities, their relationships, and key concepts, used to align stakeholders on scope and meaning before any physical design decisions are made.

Related: Logical Data Model, Physical Data Model, Entity Relationship Diagram
Logical Data Model

A detailed, platform-independent design showing entities, attributes, keys, and relationships with normalized structure and defined data types, ready to be translated into a specific database technology.

Related: Conceptual Data Model, Physical Data Model, Normalization
Physical Data Model

A technology-specific schema design covering tables, columns, indexes, partitions, constraints, and storage options tuned for a particular database engine and its performance characteristics.

Related: Logical Data Model, Denormalization, Data Partitioning
Normalization

Structuring relational tables to eliminate redundant storage and update anomalies by applying successive normal forms, each constraining dependencies among keys and non-key attributes.

Related: Denormalization, Logical Data Model, Referential Integrity
Denormalization

Deliberately introducing redundancy into a physical design, such as duplicated columns or pre-joined tables, to reduce query complexity and improve read performance at the cost of stricter write maintenance.

Related: Normalization, Physical Data Model, Dimensional Model
Dimensional Model

A design pattern organizing data into fact tables holding measures and dimension tables holding descriptive context, optimized for analytical querying and business-user comprehension rather than transactional integrity.

Related: Star Schema, Slowly Changing Dimension, Denormalization
Star Schema

A dimensional design in which a central fact table joins directly to surrounding dimension tables, keeping queries simple and predictable at the cost of some dimension redundancy.

Related: Dimensional Model, Snowflake Schema
Slowly Changing Dimension

A technique for preserving dimension history when attribute values change, using approaches such as overwriting (Type 1) or adding versioned rows with validity dates (Type 2).

Related: Dimensional Model, Data Lineage
Referential Integrity

A constraint ensuring that every value in a foreign key column matches an existing primary key value in the referenced table, preventing orphaned records and inconsistent relationships.

Related: Normalization, Entity Relationship Diagram
Entity Relationship Diagram

A visual notation depicting entities as boxes, attributes as lists, and relationships as connecting lines with cardinality markers, used to communicate data structure to technical and business audiences.

Related: Conceptual Data Model, Referential Integrity
ACID Properties

Four guarantees for transactional systems: atomicity (all or nothing), consistency (valid state transitions), isolation (concurrent transactions do not interfere), and durability (committed changes survive failure).

Related: CAP Theorem, Transaction Log
CAP Theorem

A principle stating that a distributed data system facing a network partition must sacrifice either consistency or availability, forcing architects to choose trade-offs per workload rather than achieving all three.

Related: ACID Properties, Data Replication
Data Partitioning

Dividing a large table or dataset into smaller physical segments by range, list, or hash so queries scan less data and maintenance tasks can operate on individual segments.

Related: Physical Data Model, Data Replication, Data Archiving
Data Replication

Copying data from a source system to one or more target systems or nodes to improve read scalability, availability, or locality, with defined strategies for propagating and reconciling changes.

Related: CAP Theorem, Change Data Capture, Data Partitioning
Change Data Capture

A technique that identifies and captures inserts, updates, and deletes from a source system, typically via logs or timestamps, so downstream stores can be refreshed incrementally instead of fully reloaded.

Related: Data Replication, ETL, Data Integration
Data Archiving

Moving inactive data to lower-cost storage while retaining it for legal, audit, or historical needs, with documented retrieval paths and alignment to retention schedules.

Related: Data Retention, Data Partitioning
Data Retention

The defined period for which data must be kept to satisfy business, legal, or regulatory requirements, after which it should be securely disposed of according to policy.

Related: Data Archiving, Data Policy, Data Masking
Data Masking

Replacing sensitive values with realistic but fictitious substitutes so non-production environments and broader audiences can use data without exposing protected information.

Related: Pseudonymization, Data Retention, Role-Based Access Control
Pseudonymization

Replacing direct identifiers with tokens or keys so records can still be linked for analysis, while re-identification requires separately secured mapping information.

Related: Data Masking, Personal Data
Personal Data

Any information relating to an identified or identifiable natural person, including direct identifiers and indirect combinations that can single out an individual.

Related: Pseudonymization, Data Classification, Data Minimization
Data Classification

Assigning data to sensitivity tiers such as public, internal, confidential, and restricted, which then drives handling, access, encryption, and retention requirements.

Related: Role-Based Access Control, Data Masking, Personal Data
Role-Based Access Control

Granting permissions to job-function roles rather than individuals, so users inherit the access their role requires and changes are managed centrally through role membership.

Related: Data Classification, Least Privilege
Least Privilege

A security principle limiting each user, service, or process to the minimum access needed to perform its function, reducing the blast radius of mistakes and compromised credentials.

Related: Role-Based Access Control, Data Classification
Data Minimization

Collecting and retaining only the data actually needed for a stated purpose, reducing exposure, storage cost, and compliance burden.

Related: Personal Data, Data Retention
ETL

Extract, transform, load: a pipeline pattern that pulls data from sources, applies cleansing and conforming logic in a staging area, then writes results to a target store.

Related: ELT, Data Integration, Change Data Capture
ELT

Extract, load, transform: a pattern that lands raw source data in the target platform first and applies transformations there, leveraging scalable warehouse or lakehouse compute.

Related: ETL, Data Lake, Data Integration
Data Integration

The discipline of combining data from multiple sources into a consistent, usable view through patterns such as consolidation, federation, propagation, and virtualization.

Related: ETL, Master Data Management, Data Virtualization
Master Data Management

A governed process for creating and maintaining a single trusted version of core entities such as customers, products, and suppliers across systems, resolving duplicates and enforcing shared definitions.

Related: Data Integration, Data Quality Dimensions, Data Lineage
Data Virtualization

Presenting a unified query interface over distributed sources without physically copying data, trading some performance and source availability risk for freshness and reduced duplication.

Related: Data Integration, Data Federation
Data Federation

An integration approach that queries multiple autonomous source systems at request time and combines results, leaving data in place under each source's own controls.

Related: Data Virtualization, Data Integration
Data Lineage

Documentation of data's origin and movement across systems, transformations, and reports, supporting impact analysis, root-cause investigation, and regulatory traceability.

Related: Metadata, ETL, Data Quality Dimensions
Metadata

Structured information describing data itself, such as definitions, types, owners, lineage, and usage statistics, enabling discovery, governance, and consistent interpretation.

Related: Data Dictionary, Data Lineage
Data Dictionary

A catalog of data elements with their names, definitions, data types, allowed values, and ownership, serving as the authoritative reference for interpretation and standards compliance.

Related: Metadata, Data Standard, Reference Data
Reference Data

Controlled code sets and lookup values, such as country codes or status lists, shared across systems to keep classifications consistent and comparable.

Related: Data Dictionary, Data Standard
Data Quality Dimensions

Measurable characteristics used to assess fitness for use, commonly including completeness, accuracy, consistency, timeliness, uniqueness, and validity, each with defined thresholds and owners.

Related: Data Profiling, Data Cleansing, Data Stewardship
Data Profiling

Analyzing datasets statistically to reveal structure, value distributions, null rates, duplicates, and pattern anomalies, establishing a baseline before quality rules are defined.

Related: Data Quality Dimensions, Data Cleansing
Data Cleansing

Correcting, standardizing, or removing inaccurate and inconsistent records, ideally at the source, with documented rules and audit trails to prevent recurrence.

Related: Data Profiling, Data Quality Dimensions
Data Federation

An integration pattern where a virtual layer queries multiple source systems on demand and merges the results, avoiding physical copies but depending on source availability and performance.

Related: Data Virtualization, Data Integration
Data Lake

A centralized repository storing raw and refined data in native formats at scale, typically supporting diverse analytics workloads and requiring cataloging and governance to remain usable.

Related: ELT, Metadata, Data Archiving