1. SQL Compare & SQL Refactor
András Belokosztolszki
12/03/2008

2. András Belokosztolszki
Software architect at Red Gate Software
Responsible for SQL tools:
SQL Compare
SQL Log Rescue
SQL Refactor
… many others
Events (User groups, SQL Bits)
SQL Server Central
Blog:
Articles:

3. Agenda Two case studies Motivation Features Demo Problems SQL Compare
SQL Refactor
Motivation
Features
Demo
Problems

4. SQL Compare
Compares and synchronizes the schemata of two SQL Server databases.
Flagship product
Started as a side-project

5. Database Development Development on the database
Compare development database with production/staging database
Synchronize/Deploy
This is very similar to application development, but

6. DEMO
How to install (standalone application, single ext stored procedure)
First the add/modify/delete
More stuff (show how the UI works:
- many rows
- scroll
- filter
- sort
- time range
- group by!!!

7. Challenges SQL Server 7, 2000, 2005, 2008 system tables differ
Object dependencies - ordering
Textual objects (with options)
Defaults
DBO; to read all meta information
Table rebuilds (identity)
Double table rebuilds (partition schemes)
CLR Assemblies and rules for their alters
Unnamed constraints
Impossible cases (default not null)

8. Difficulties Complex object dependencies Complex rebuild conditions
25 object types, long dependency chains
Complex rebuild conditions
Massive databases
PeopleSoft:
200,000 stored procedures
6.8M parameters
23,000 tables

9. DB Development Problems:
It is NOT compiled code with public/private qualifiers
Dependencies can be broken
Where are these? What is using this object? Public API
Can I modify this?
What is in this object?
Who changed this the last time?
Problems are detected during production?
Garbage (unused, possibly unusable code, possibly maintained)
Documentation: Where to store? How to retrieve?
Legacy code
No versioning
No audit
Data

10. Database Development With Problems
Development on development databases/files
Where is the schema stored during development
Explore
What is in the database
Where is the schema stored in the database
Compare
Are two objects the same?
Processed objects (e.g. defaults and constraints)
Generated objects (e.g. symmetric keys)
Synchronize/Deploy Problems:
Data
CLR Assemblies
Permissions/users

11. Where Is the Schemata Stored?
In the database itself
Modified directly
Table columns are added
Stored procedures added
Some validation by SQL Server
Execute procedures
Query views
Source control integration is hard
Garbage
Creation scripts
All development is on SQL files
Can be stored in source control
Audit log (who, when, what)
Validation is a problem
Data? Scripts need to populate data
MS Data Dude; SQL Compare 6.0
Where Is the Schemata Stored?
SQL Compare 6.0; DataDude; MS push ?

12. Source Control For Databases
Source control works with files, the database schema is not in files
Problem: identifying the difference between the files and the database schema itself
Problems: keeping the files in sync with the database

13. Reading Backup Files Large demand Backup format is proprietary
Database files do differ (2000, 2005, 2008)

14. SS2008 Support Many new features and changes
POWERSUM private (system function)
FILESTREAM -> Table build order
COLUMNSETS

15. Development History (Neil, Me, team) Other projects depending on us
SQL Data Compare
SQL Dependency Tracker
SQL Refactor
SQL Data Generator
SQL Doc
SQL Prompt
SQL Packager
SQL Toolkit
SQL Changeset
Continuous integration
1-1 dev/tester
Unit testing (over nightly tests, 4-5 servers, daily reports)

16. SQL Refactor Productivity tool for SQL Server Lay out SQL Smart Rename
Smart column rename for views and tables
Smart parameter rename for procedures and functions
Split Table, can also create referential integrity tables
Uppercase Keywords
Summarize Script
Expand Wildcards in SELECT statements
Qualify Object Names
Find Unused Variables and Parameters
Encapsulate As New Stored Procedure

17. DEMO
How to install (standalone application, single ext stored procedure)
First the add/modify/delete
More stuff (show how the UI works:
- many rows
- scroll
- filter
- sort
- time range
- group by!!!

18. Problems and Challenges
Management Studio Extensibility
DDL Hell in .Net
About 20 refactorings, priorities
No other tools like this on the market
Some refactorings are complex (Table Split)
Lay Out (we support nearly 40 options, but is this enough?)

19. Table Split Motivation: The table rows are very large
The database design is changing, and an entity is separated into two with a 1:N or M:1
Domain restriction needs to be added retrospectively

20. ? Questions Andras.Belokosztolszki@red-gate.com