Real Application Testing = SPA + Database Replay
SPA和 Database Replay的区别：
Database Replay好比是给鸭梨山大的锤子：
SPA: SQL focused and unit testing SQL component
Database Replay: Workload focused, comprehensive testing of database stack
Database Replay
Load testing solution for performance and scalability testing
"Capture" entire workload (queries, DML, DDL, PL/SQL, etc.) in production, including concurrency
"Replay" entire workload in test with exact production characteristics including concurrency
Ideal for system upgrades, configuration changes (SI to RAC), storage changes, etc.
SPA还比是好用的起钉锤：
SQL Performance Analyzer
Solution for identifying performance regressions/improvements resulting from execution plan changes
"Capture" SQL queries from production, including executions plans & stats
"Test-Execute" SQL queries serially "before" and "after" changes
Compare "before" and "after" SQL execution plans and performance stats
Ideal for changes impacting query plans such as db upgrades, optimizer statistics refresh, new index creation, etc.
Real Application Testing RAT作为DBEE(企业版)数据库的选项来销售， 单独使用SPA或Database Replay均要求购买完整的RAT使用许可证。
RAT的具体价格为$11,500/cpu ($230/NUP Named User Plus)，无论是产品还是测试数据库。
注意当从9iR2或10gR1升级到10gR2时，SPA要求使用在9iR2或10gR1的产品数据库上使用SQL TRACE功能以便捕获SQL语句。仅在此场景中，RAT license仅对测试系统有效而非产品系统。
SQL Performance Analyzer
Capture on 9i, 10.1, 10.2 database releases
Test changes in 10.2 & above
Database Replay
Capture on 9i, 10.2 database releases
Test changes in 11.1 & above