SQL Database migration

Graphical demonstration of

Why we should use

“Database Aliases”

SQL1

App1

db2

db1

App2

SQL1

App1

db2

db1

App2

Connect to SQL1

Connect to SQL1

Provider=SQLOLEDB; Data Source=SQL1; Database=db1;Integrated Security=SSPI

SQL1

App1

db2

db1

App2

SQL2

Connect to SQL1

Connect to SQL1

SQL1

App1

db2

db1

App2

SQL2

db2

Connect to SQL1

Connect to SQL1

SQL1

App1

db1

App2

SQL2

db2

Connect to SQL1

Connect to SQL2

Update App2 config

Using a Database Alias

• Alias can only point to an Instance.

• It does not point to a database.

• Each database now have an alias that point to the same server.– Alias1 = SQL1 (meant to reach db1)– Alias2 = SQL1 (meant to reach db2)

SQL1

App1

db1

App2db2

Connect to Alias1

Connect to Alias2

Provider=SQLOLEDB; Data Source=Alias1; Database=db1;Integrated Security=SSPI

SQL1

App1

db1

App2

SQL2

db2

Connect to Alias1

Connect to Alias2

db2

SQL1

App1

db1

App2

SQL2

Connect to Alias1

Connect to Alias2

Upd

ate

Ali a

s2=S

QL2

db2

Any questions?