Design innovative, scalable, and highly available cloud database solutions →hardMultiple SelectObjective-mapped
PCDE Practice Question: Design innovative, scalable, and highly available cloud database solutions
A company wants to migrate a 5 TB MySQL database to Cloud Spanner with zero downtime. They need to validate schema and data consistency before switching traffic. Which THREE steps should they include in the migration plan?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Set up a Dataflow pipeline to replicate changes from MySQL to Spanner
Zero-downtime migration to Spanner typically involves using Strangler Fig pattern: replicate writes from MySQL to Spanner, validate data, then cutover. Key steps: 1. Export schema and convert to Spanner DDL (using HarbourBridge). 2. Set up live migration using Dataflow for continuous replication. 3. Validate data consistency (e.g., using checksums). Taking an export snapshot is fine but not for zero-downtime; using pgloader is for PostgreSQL; creating a Cloud SQL read replica is not directly relevant.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Set up a Dataflow pipeline to replicate changes from MySQL to Spanner
Why this is correct
Dataflow can stream changes for near real-time replication.
- ✗
Use pgloader to migrate the data
Why it's wrong here
pgloader is for PostgreSQL, not MySQL.
- ✗
Create a Cloud SQL read replica for fallback
Why it's wrong here
Read replica is unnecessary; the goal is to migrate to Spanner.
- ✓
Use HarbourBridge to convert MySQL schema to Spanner DDL
Why this is correct
HarbourBridge helps convert and export schema and data.
- ✓
Validate data consistency between MySQL and Spanner using checksums
Why this is correct
Validation ensures data integrity before cutover.
Go deeper
Related to this question
About these practice questions
This PCDE question is part of Courseiva's 1,446-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This PCDE practice question is part of Courseiva's free Google Cloud certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PCDE exam.