This presentation about common problems with data base versioning, migration and maintaining during project live cycle. Also we will look at useful tools that can help us to solve these problems. Then we will compare two most popular tools Liquibase and Flyway , and run live demo with small migration using one of them.

2. why: versions
Data Base migration:
Data base structure:
- Tables, constrains, indexes;
Data base data:
v1.0.0

3. why: versions
Data Base migration:
Data base structure:
- Tables, constrains, indexes;
Data base data:
- Initial data like list of post co
v1.2.1
v1.0.0

4. Data Base migration:
Data base structure:
- Tables, constrains, indexes;
Data base data:
- Initial data like list of post
v1.2.1
v1.6.0
v1.0.0
why: versions

5. Data Base migration:
Data base structure:
- Tables, constrains, indexes;
Data base data:
- Initial data like list of post c
v1.2.1
v1.6.0
v2.0.1
v1.0.0
why: versions

6. Data Base migration:
Data base structure:
- Tables, constrains, indexes;
Data base data:
- Initial data like list of post codes,
statuses for order, etc.
Data base logic:
- stored procedures, triggers, functions
v1.2.1
v1.6.0
v2.0.1
v1.0.0
why: versions

7. Data Base migration:
Data base structure:
- Tables, constrains, indexes;
Data base data:
- Initial data like list of post codes,
statuses for order, etc.
Data base logic:
- stored procedures, triggers, functions
v1.2.1
v1.6.0
v2.0.1
v1.0.0DEV
why: environments

8. Why: data
Database migration:
Database structure:
- Tables, constrains, indexes;
Database data:
- Initial data like list of post codes,
statuses for order, etc.
Database logic:
- stored procedures, triggers, functions

9. Conclusion
We need version control
over our database
migration

10. Tools
Play framework:migration
Rails ActiveRecord
migrations
Mogeez for

11. Tools
Play framework:migration
Rails ActiveRecord
migrations
Mongeez for

12. Tools
Play framework:migration
Rails ActiveRecord
migrations
Mogeez for

13. Tools
Play framework:migration
Rails ActiveRecord
migrations
Mogeez for

14. Tools
Liquibase :
•Apache license
•Started in 2006 (active)
•http://liquibase.org
Flyway:
•Apache license
•Started in 2010
•http://www.flywaydb.org

15. Common flow
Build Test Run
• Dev
• Test
• Acceptance
• Production
• GUI tests
• Integration
tests
• API tests
• Unit tests
• Ant
• Maven
• Gradle

16. Common flow
Build Test Run
• Dev
• Test
• Acceptance
• Production
• GUI tests
• Integration
tests
• API tests
• Unit tests
• Ant
• Maven
• Gradle

17. Common flow
Build Test Run
• Java API
• Spring Bean
• Plugins
• CLI
• Plugins
• CLI

18. Supported formats
DSL for database
changes:
• XML
• YAML
• JSON
• sql
Pure SQL

19. How it works
V1__Initial_Setup.sql
V1_1__First_Changes.sql
V1_2__Added_user_info.sql
V2__ ….

20. How it works
Schema_versions:

21. How it works
Changes are grouped into changesets:
• Change(s) that should be applied
atomically
Changesets are grouped into
changelogs:
•Files managed in version control

22. How it works
v1_changeLog.xml
v1.1_changeLog.xml
v2_changeLog.xml
v1.2_changeLog.xml
v1.3_changeLog.xml
v2.1_changeLog.xml
…

23. How it works
DatabaseChangelogLock:
DatabaseChangelog:

24. Supported db list
MySQL
PostgreSQL
Oracle
MSSQL Server
Sybase_Enterprise
Sybase_Anywhere
DB2
Apache_Derby
HSQL
H2
Informix
Firebird
SQLite
MySQL
PostgreSQL
Oracle
MSSQL Server
SQL Azure
MariaDB
Phoenix
Vertica
AWS Redshift
DB2, DB2 z/OS
Derby
H2, Hsql, SQLite, SAP HANA,
solidDB, Sybase ASE

25. Base line
Convention over
configuration
Toolbox

26. Toolbox
• Rollback
• Context
• SQL output
• Precondition

27. Toolbox: precondition
<preConditions onFail="WARN" onError="MARK_RAN">
<dbms type="oracle"/>
<runningAs username="SYSTEM"/>
<tableExists tableName=“newTable"/>
<customPrecondition className=“com.example.CheckOne"/>
<sqlCheck expectedResult="0">
select count(*) from oldtable
</sqlCheck>
</preConditions>

28. Toolbox: precondition
<preConditions onFail="WARN" onError="MARK_RAN">
<dbms type="oracle"/>
<runningAs username="SYSTEM"/>
<tableExists tableName=“newTable"/>
<customPrecondition className=“com.example.CheckOne"/>
<sqlCheck expectedResult="0">
select count(*) from oldtable
</sqlCheck>
</preConditions>

29. Toolbox: precondition
<preConditions onFail="WARN" onError="MARK_RAN">
<dbms type="oracle"/>
<runningAs username="SYSTEM"/>
<tableExists tableName=“newTable"/>
<customPrecondition className=“com.example.CheckOne"/>
<sqlCheck expectedResult="0">
select count(*) from oldtable
</sqlCheck>
</preConditions>

30. Toolbox: precondition
<preConditions onFail="WARN" onError="MARK_RAN">
<dbms type="oracle"/>
<runningAs username="SYSTEM"/>
<tableExists tableName=“newTable"/>
<customPrecondition className=“com.example.CheckOne"/>
<sqlCheck expectedResult="0">
select count(*) from oldtable
</sqlCheck>
</preConditions>

31. Toolbox: precondition
<preConditions onFail="WARN" onError="MARK_RAN">
<dbms type="oracle"/>
<runningAs username="SYSTEM"/>
<tableExists tableName=“newTable"/>
<customPrecondition className=“com.example.CheckOne"/>
<sqlCheck expectedResult="0">
select count(*) from oldtable
</sqlCheck>
</preConditions>

32. Toolbox: precondition
<preConditions onFail="WARN" onError="MARK_RAN">
<dbms type="oracle"/>
<runningAs username="SYSTEM"/>
<tableExists tableName=“newTable"/>
<customPrecondition className=“com.example.CheckOne"/>
<sqlCheck expectedResult="0">
select count(*) from oldtable
</sqlCheck>
</preConditions>

33. Toolbox: precondition
<preConditions onFail="WARN" onError="MARK_RAN">
<dbms type="oracle"/>
<runningAs username="SYSTEM"/>
<tableExists tableName=“newTable"/>
<customPrecondition className=“com.example.CheckOne"/>
<sqlCheck expectedResult="0">
select count(*) from oldtable
</sqlCheck>
</preConditions>

34. DEMO

35. Structure:
v1.0

36. Structure:
v1.0

37. Structure:
v1.0 v2.0

38. Structure:
v1.0 v2.0

39. LET US DO IT

40. Best practice

41. Sequential change flow
1. Init db
2. Add column “type”
3. Add new table

42. Sequential change flow
1. Init db
2. Add column “type”
3. Add new table

43. Sequential change flow
1. Init db
3. Add new table
4. Remove column “type”
2. Add column “type”

44. Repeatable changes
applied
first
applied
last

45. Versioning
v1.2 v1.3 v2.0v1.1

46. Versioning
v1.1 v1.2 v1.3 v1.4 v2.0 v2.1
v1.2.1
v1.2.2
v1.3.1
v1.3.2
v1.3.1.1
v1.3.3

47. V1.2 V1.3V1.1
Versioning
v1.2 v1.3 v2.0v1.1

48. Do backup

49. Thank you for attention
Q & A
uholnikovroman@gmail.com
Code of presentation:
https://bitbucket.org/Roman-Ugolnikov/db-migration-demo