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275 questions, 991 terms and 600 topics in 30 areas.
25 results for “Slowly Changing Dimensions”
Slowly Changing Dimension
A strategy for handling attributes that change over time, deciding whether history is preserved and how facts attach to the correct version.
Attribute History Strategy
The per-attribute decision about whether history is overwritten, versioned or kept alongside the current value, which is a business question rather than a technical one.
Ambassador Pattern
A helper process that handles outbound network communication on behalf of an application, adding retries, routing, security and telemetry without changing it.
Event Sourcing
Storing the full sequence of state-changing events as the system of record, and deriving current state by replaying them.
Expand-Contract Migration
Changing a schema in additive steps that keep old and new code both working, so deployment and migration never have to be simultaneous.
Hub and Satellite
Separating stable business keys from their changing attributes and from their relationships, so each can be loaded independently and kept forever.
Inner Loop Latency
The time from changing a line to observing its effect, repeated dozens of times a day and therefore the highest-leverage number in developer experience.
Managed Service Substitution
Replacing a self-managed component with a managed equivalent during migration, without changing the application's architecture.
Quality Dimension Threshold
The stated numeric level at which a dataset is fit for its purpose on a given quality dimension, plus what happens when it is not met.
Refactoring
Changing the internal structure of code without changing its external behaviour, in small verified steps.
Refactoring Under Test
Changing internal structure without changing behaviour, with tests as the mechanism that makes the claim verifiable.
Schema Evolution
Changing a table's structure over time while keeping existing data readable and existing consumers working.
Sidecar
Deploying a helper process alongside the main application in the same unit, to supply cross-cutting behaviour without changing the application.
Technology Evaluation Criteria
A standing set of dimensions for assessing a candidate technology, ensuring that operability and longevity are weighed alongside capability.
Zero-Downtime Migration
Changing a schema or system while it stays in service, by adding the new alongside the old, migrating, then removing the old.
A team wants to move a workload from PostgreSQL to a document store because "the schema keeps changing". What do you ask?
The questions 1. What is actually changing — the shape, or the schema management process? "The schema keeps changing" usually means migrations are painful, not
One instance in a fleet of fifty is returning correct responses very slowly. Health checks pass and it stays in rotation. How do you detect and handle this?
Why it is not detected Differential observability. The instance believes it is healthy and reports so; its callers experience something else. A health check tha
You are setting data quality thresholds for a dataset with five consuming teams. How do you decide the numbers?
Not by the data team, and not one number for everyone Fitness for purpose differs by consumer. Ninety five percent completeness on an attribute is fine for a ma
Slowly Changing Dimensions
Overwriting, versioning or timestamping attribute history, and the reporting each enables.
Data Quality Dimensions
Completeness, accuracy, timeliness, consistency, validity and uniqueness as testable claims.
Dimensional Modelling
Facts, dimensions, grain, and the star schema's continued relevance.
Refactoring
Changing structure without changing behaviour, in verified steps.
Refactoring & Re-architecting
Changing structure incrementally while the system keeps running.
Security Design Review
Reviewing an architecture for security while changing it is still cheap.
Streaming Schema Evolution
Changing an event's shape while a retained log still holds every older version of it.