SQL Server Team-based Development - Red Gate Software

Chapter 3: Change Management and Source Control
method is to create an authoritative source database; a database you would treat like a
production system, where you maintain what your source data should look like. You can
add effective dates, expiration dates, and flags to determine if a piece of data is ready for
a production rollout. A basic lookup table, consisting of an ID/Value pair, would look
something like the one in Listing 3-3.
CREATE TABLE dbo.IvLookup
(
ID INT NOT NULL IDENTITY(1,1) ,
IvValue NVARCHAR(50) NOT NULL ,
EffDate DATETIME NOT NULL ,
ExpDate DATETIME NULL ,
ProductionReady BIT NOT NULL ,
IsDeleted BIT NOT NULL ,
AppLabel NVARCHAR(30) NOT NULL ,
PRIMARY KEY CLUSTERED ( ID )
);
Listing 3-3: A lookup table in the authoritative source database.
The data stored in a table following this approach allows for a number of control points
to help dictate which data is ready for use in various environments. The ID and IVvalue
columns for the lookup information are the easiest to describe. These would be artificial
keys and associated values that provide the lookup information. The effective and
expiration dates, EffDate and ExpDate, can be used to return only data that is active
within a given time period. The bit fields ProductionRead and IsDeleted can be
used to mark a value as being either ready for release to production, or logically deleted.
Logical deletion is the best way to maintain data integrity and yet remove lookup values
from active lists within the application. By labeling the software version that last updated
the value, AppLabel, the data can be associated with a particular rollout, especially when
the deployments are incremental, meaning that we are only deploying changes rather
than performing a complete redeployment of a database.
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