The database executes all the required SQL and logic using the
parameters it receives.
Stored procedures can also shield the client logic from internal changes to the data
structures or program logic. As long as the parameters the client passed in and
received back don??™t change, no changes are required in the client software. Stored
procedures move a portion of the application logic from the client to the database
server. By doing so, stored procedures can reduce the network traffic considerably.
This capability increases the scalability of two-tier systems. Figure 9-2 illustrates a
two-tier system with stored procedures.
Figure 9-1. Two-tier client/server architecture
Figure 9-2. Two-tier system with stored procedures
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Database
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Procedure Calls
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208 | Chapter 9: Oracle and Transaction Processing
Three-Tier Systems
The OLTP systems with the largest user populations and transaction throughput are
typically deployed using a three-tier architecture.
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