Schemachange
Deploy and manage Snowflake database changes using version control and CI/CD pipelines with schemachange's migration-based approach.
Quick Start
Script Types:
- V__ (Versioned) - One-time structural changes (run exactly once)
- R__ (Repeatable) - Objects that can be safely recreated (runs when new/modified)
- A__ (Always) - Scripts that run every deployment (must be idempotent)
Script Naming
Versioned Scripts (V__)
sql1V1.0.0__initial_setup.sql 2V1.1.0__create_base_tables.sql 3V2.0.0__restructure_schema.sql
Use for: CREATE TABLE, ALTER TABLE, CREATE SCHEMA
Repeatable Scripts (R__)
sql1R__Stage_01_create_views.sql 2R__Stage_02_alter_procedures.sql 3R__Stage_03_utility_functions.sql
Use for: CREATE OR ALTER VIEW, CREATE OR ALTER PROCEDURE, CREATE OR REPLACE STREAM
Always Scripts (A__)
sql1A__refresh_permissions.sql 2A__update_config_values.sql
Use for: Jobs that must run every deployment (idempotent only)
Key Concepts
Execution Order
- Versioned scripts (V__) in numeric order
- Repeatable scripts (R__) in alphabetic order (use naming to control)
- Always scripts (A__) in alphabetic order
CREATE OR ALTER vs CREATE OR REPLACE
- CREATE OR ALTER - Preserves data, tags, policies, grants (preferred)
- CREATE OR REPLACE - Drops and recreates (loses metadata)
See CREATE_OR_ALTER_REFERENCE.md for supported objects.
Configuration
yaml1# schemachange-config.yml 2root-folder: migrations 3create-change-history-table: true 4connection-name: default 5change-history-table: MY_DB.SCHEMACHANGE.CHANGE_HISTORY
Deployment
bash1# Dry run 2schemachange deploy --config-folder . --dry-run 3 4# Deploy 5schemachange deploy --config-folder . 6 7# With variables 8schemachange deploy --vars '{"env":"prod","schema":"data"}'
Resources
schemachange-config.yml- Complete configuration templateSCRIPT_PATTERNS.md- Examples for V**, R**, A__ scripts (coming soon)CREATE_OR_ALTER_REFERENCE.md- Supported object types (coming soon)CI_CD_EXAMPLES.md- GitHub Actions and Azure DevOps patterns (coming soon)
