Database Migration
Everything on SkillVeris tagged Database Migration — collected across the glossary, study notes, blog, and cheat sheets.
11 resources across 1 library
Interview Questions(11)
How Do You Design a Zero-Downtime Database Migration?
A zero-downtime database migration succeeds by decomposing a risky single cutover into small, reversible, backward-compatible steps — expand the schema, dual-w…
What Are Schema Versioning Tools and Why Use Them?
Schema versioning tools track every database schema change as an ordered, version-controlled migration file, so a database's structure can be reliably reproduc…
How Does Blue-Green Deployment Apply to Databases?
Blue-green deployment for databases means maintaining two full environments — the live blue database and an idle green database with the new schema and data fu…
What Makes a Database Schema Change Backward-Compatible?
A backward-compatible schema change is one that old application code, already deployed and still running, can continue to read and write correctly after the ch…
What Are Online Schema Change Tools and How Do They Work?
Online schema change tools such as gh-ost and pt-online-schema-change let you alter a large production table — add a column, change an index — without holding…
How Do You Design a Rollback Strategy for Schema Migrations?
A safe rollback strategy pairs every forward migration with a tested, reversible 'down' script or an expand-contract sequence, so a failed deploy can restore t…
What Makes a Database Migration Idempotent, and Why Does It Matter?
An idempotent migration produces the same final schema and data state no matter how many times it is run or re-run, so retries after a partial failure never du…
How Do You Manage Seed Data Across Environments?
Seed data should be managed as versioned, idempotent scripts checked into source control, with a clear split between environment-agnostic reference data needed…
What Are the Key SQL Dialect Differences Between MySQL and PostgreSQL?
MySQL and PostgreSQL both implement standard SQL but diverge in string quoting rules, auto-increment syntax, upsert syntax, data types, and how strictly they e…
What are Kubernetes Init Containers?
Init containers are one or more containers defined in a Pod spec that run to completion, in order, before any of the Pod’s main application containers start, t…
How Do You Safely Run Database Migrations in a CI/CD Pipeline?
Safe database migrations in CI/CD rely on the expand-contract pattern: first deploy a backward-compatible schema change that both old and new application code…