Data Dictionary
A data dictionary is a centralized reference that documents every table and column in a database—what it contains, what its values mean, and how it should be used.
In Depth
A schema tells you a column is called "status" and holds integers; a data dictionary tells you that 1 means trial, 2 means active, and 3 means churned-but-recoverable. That institutional knowledge usually lives in the heads of two engineers, which is why new analysts take weeks to write trustworthy queries. A maintained data dictionary makes the database legible to humans—and increasingly to AI, since the same descriptions that help a new hire also dramatically improve an AI's ability to translate business questions into correct SQL.
How AI for Database Helps
AI for Database builds its understanding from your schema and available descriptions, so documented databases get even more accurate answers.
Related Terms
Column Descriptions
Column descriptions are human-readable annotations attached to database columns that explain what each column contains and how its values should be interpreted.
Business Glossary for AI
A business glossary for AI is a curated set of definitions for company-specific terms—what counts as an "active user", how "revenue" is calculated—provided to an AI system so it interprets questions the way the business does.
Schema
The structural blueprint of a database that defines tables, columns, data types, relationships, and constraints.
Metric Definition
A metric definition is the precise, agreed specification of how a business metric is calculated—which tables, filters, and formulas produce numbers like MRR, churn rate, or active users.
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