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Data quality monitoring guide for reliable analytics

How to know if the data behind your decisions is actually good

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Every company and team runs on data. You need data to make decisions, prioritize work, and understand what's actually happening in your business. But the quality of those decisions depends entirely on the quality of that data. Which is why data quality monitoring needs to be a core function of any data organization.

This guide goes over what data quality monitoring means, what exactly to monitor, and how to do it the traditional way and with the help of AI.

What is data quality monitoring?

Data quality monitoring is the continuous process of checking whether your data meets the requirements of its intended use. It’s a continuous process, not a one-and-done deal, meaning you need to create automated systems that regularly assess data fitness across pipelines, transformations, and consumption points.

What counts as "quality" depends on your context. "Good quality" for a marketing dashboard might not cut it for financial reporting or training AI models. What you're using the data for determines whether it's good enough.

In short, everyone who touches data has a role to play in data quality monitoring:

  • Data engineers monitor pipeline reliability and schema validation, ensuring data flows correctly from source to warehouse

  • Analytics engineers monitor metric definitions and transformation logic, maintaining the semantic layer that defines business calculations

  • Data analysts validate analysis outputs, catching issues where technically correct queries produce semantically wrong answers

  • Business stakeholders monitor the data they consume directly, flagging suspicious trends or unexpected changes in their dashboards and reports

  • Platform teams monitor AI systems themselves, ensuring they generate semantically appropriate queries, not just syntactically valid SQL

With the right monitoring approach, you can enable both technical and non-technical users to explore data confidently, knowing the answers they get are not just structurally valid but semantically appropriate for the questions they're asking.

Which data quality metrics should you monitor?

Data quality monitoring requires tracking both structural correctness and semantic appropriateness.

Structural dimensions validate that data matches its schema and arrives reliably. Semantic dimensions validate that the data means what people think it means when they query it.

Most teams start with structural monitoring through tracking traditional dimensions, then add semantic monitoring as their data infrastructure matures and governance becomes critical.

Six traditional dimensions catch structural problems in your data. These align with established data governance frameworks that define quality standards across organizations:

  1. Accuracy: Whether data correctly reflects the real-world values it represents, matching authoritative sources

  2. Completeness: Whether all needed data elements are present without unexpected null values or missing records

  3. Consistency: Whether data remains uniform across different systems, time periods, and representations

  4. Timeliness: Whether data is current and available when needed for decision-making

  5. Validity: Whether data conforms to defined formats, rules, and acceptable value ranges

  6. Uniqueness: Whether records appear only once unless intentional duplication is needed by the data model

These dimensions ensure your data matches its schema, follows data type requirements, maintains referential integrity, and arrives on schedule. Without monitoring these basics, data quality can erode. Meaning queries return incorrect results, dashboards show misleading trends, and decisions get made on fundamentally broken information.

Structural correctness doesn't guarantee semantic correctness, though. Data can pass all six traditional checks while still producing wrong answers because the underlying logic doesn't match the intended question. This happens when metric definitions differ across teams, tables lack clear production status indicators, or joins aggregate data inappropriately without proper context.

Three additional dimensions address these semantic concerns:

  1. Semantic clarity: Whether metrics are defined consistently across teams and tools so everyone calculates the same thing

  2. Source trustworthiness: Whether tables are clearly labeled as production-ready versus experimental or deprecated

  3. Contextual completeness: Whether sufficient metadata exists to explain how data should be properly aggregated, filtered, or joined

The most effective monitoring approach combines both types. Traditional metrics catch broken pipelines and malformed data before they cause downstream problems. Semantic dimensions catch cases where technically correct queries produce business-inappropriate answers. Organizations typically implement structural monitoring first since it requires less organizational coordination, then layer in semantic monitoring as governance needs grow.

Traditional data quality monitoring techniques

Traditional data quality monitoring techniques form the foundation of any data quality program, catching broken pipelines and malformed data before they cause downstream problems. They work best for validating structural correctness. And measure whether data matches its schema, arrives on time, and maintains referential integrity across systems.

Data teams rely on five core monitoring techniques:

  1. Data profiling with validation rules examines data characteristics and enforces business constraints. These run continuously and populate system views that enable alerting when quality thresholds are violated.

  2. Anomaly detection identifies statistical outliers and unexpected patterns. This combines statistical methods like z-score analysis and moving average comparisons with machine learning approaches such as time-series forecasting and clustering algorithms.

  3. Data lineage tracking maps how data flows through your systems from origin to consumption. It captures data sources, transformation logic, data movement between systems, and downstream dependencies (i.e., the consumers that rely on the data).

  4. Schema monitoring validates data structure at ingestion, catching schema violations early and preventing malformed data from propagating through pipelines.

  5. Integration into CI/CD pipelines embeds data quality checks directly into development workflows, enforcing data contracts and validating source data before transformations run.

Together, these traditional techniques establish baseline trust in data. But as data volume, velocity, and complexity grow, they struggle to scale without automation, which is where AI-powered data quality monitoring techniques come into play.

AI-powered data quality monitoring

AI accelerates data quality monitoring by handling pattern detection at scale. Instead of manually defining thresholds for every quality check, AI learns expected patterns from your data and flags deviations automatically. This means you can monitor entire datasets rather than just samples, catch multivariate patterns that humans miss, and identify quality issues in real-time as data arrives.

The key difference between AI and traditional monitoring is automated baseline learning. Traditional monitoring needs someone to define "revenue should be between X and Y" for every metric you track. AI establishes these baselines automatically by analyzing your data, then continuously monitors against those learned patterns.

When something breaks from the norm — e.g., revenue suddenly doubles, null values spike in a critical column, or record counts deviate from historical patterns — AI flags it immediately.

When evaluating AI analytics tools, look beyond initial accuracy to how easily you can add and refine context over time. Tools that nail a demo with pre-configured questions often struggle when real users ask questions the system wasn't optimized for. The data team's workflow for monitoring question quality, flagging incorrect answers, and improving context matters as much as the AI's out-of-the-box performance. If correcting a wrong answer takes hours of configuration rather than minutes, the system won't scale.

You can apply AI to both traditional and semantic quality dimensions:

For traditional dimensions (accuracy, completeness, consistency), AI handles anomaly detection across your pipelines. It learns what "normal" looks like for each table and column, then alerts you when data arrives that doesn't match those patterns. AI can catch broken pipelines, schema changes, and data corruption without needing you to manually define quality rules for every field.

For semantic dimensions (semantic clarity, source trustworthiness, contextual completeness), AI needs structured business context to work effectively. This is where semantic layers become critical infrastructure. When AI systems have access to your metric definitions, table lineage, and business logic, they can validate not just structural correctness but semantic appropriateness — whether a query actually answers the intended question.

Keep in mind that AI monitoring depends on quality input data. Poor data quality degrades AI effectiveness, creating a bootstrapping problem. AI works best as an augmentation for teams with foundational quality practices already in place, not as a first step for organizations lacking basic controls.

Addressing semantic quality concerns requires infrastructure beyond traditional monitoring tools. Semantic layers — which centralize metric definitions and business logic — provide the foundation for monitoring semantic appropriateness. This is where platforms with integrated semantic capabilities become valuable.

Monitor data quality in production with Hex

AI makes data quality monitoring more effective, but it only works when you integrate it naturally into how your team actually works. The most powerful approach combines AI-assisted monitoring with unified analytics environments where data quality checks happen automatically as part of your normal process, not as separate operational overhead you have to remember to do.

Hex is an AI-native analytics platform that makes it easy to do data quality monitoring directly in your workspace. Unlike tools that bolt on AI capabilities as an afterthought, Hex's AI is built throughout the platform with full access to your data warehouse schemas, semantic models, and metric definitions. This native integration means both humans and AI work from the same trusted foundation.

Here's how Hex supports data quality monitoring.

Governance tools guide both humans and AI. Data teams can set up context that steers users and agents toward trusted sources. Endorsed statuses signal which tables to prioritize. Workspace guides capture tribal knowledge—business terminology, metric selection criteria, data quirks—that doesn't live in your database. Warehouse descriptions provide foundational context on tables and columns. And semantic models enforce rigid rules when metrics must be calculated exactly the same way every time.

Unified workspace eliminates context loss. Data quality problems get lost when you're jumping between SQL, dashboards, presentations, and notebooks that weren't meant to be used with each other. Hex consolidates these workflows into one environment where monitoring happens naturally as you work. Features like Explore let both technical and non-technical users work from the same trusted data.

Semantic layer ensures consistency. When you define metrics once in your dbt semantic layer, both humans and AI query against those definitions instead of raw tables. This means everyone calculates metrics the same way, which eliminates the "which number is right?" debates that erode trust in data.

Real-time collaboration catches issues faster. Multiplayer editing means quality issues get caught and fixed with full visibility into who changed what and when. Data teams maintain governance over definitions, lineage, and metric calculations while business users gain the independence to explore data confidently.

The work shifts from firefighting data quality issues to building systems that earn trust. Everyone works from the same foundation, with the same definitions, in the same collaborative environment. That's where interesting work happens: building infrastructure that scales, earning credibility across the organization, and focusing on strategic analysis instead of answering the same questions repeatedly.

Get started with Hex or request a demo to see how native AI integration changes the way your team does data quality monitoring.

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