Bookshelf v7.7: About Midtier-Centric and Mainframe-Centric Development Environment Upgrades

Historically, all development environment upgrades have been done from the midtier (midtier-centric) and applied to the z/OS host using Windows- or UNIX-based client-side tools. In Release 7.7, the development environment upgrade has been enhanced to allow for all DDL (CREATE, DROP, DELETE, ALTER, and GRANT) and DML (INSERT, UPDATE, DELETE, and SELECT) to be executed on the mainframe host. Based on your business requirements, you can choose to perform either a midtier-centric or mainframe-centric development environment upgrade. Table 7 lists some of the advantages and disadvantages of each type of upgrade.

NOTE: By default, the Siebel software contains the midtier-centric development environment upgrade files. If you want to perform a mainframe-centric development environment upgrade, you need to copy and replace these files in order to generate the appropriate upgrade output files.

Table 7. Midtier-centric and Mainframe-centric Environment Upgrades
Upgrade	Advantage	Disadvantage
Midtier-centric development environment.	This type of upgrade follows previous Siebel upgrade flows and allows you to work with existing expertise.	This type of upgrade does not allow you to take advantage of any enhancements that were built into the mainframe-centric development environment upgrade.
Mainframe-centric development environment.	You can build a level of experience with this type of upgrade that can be leveraged during your production environment upgrade.	This type of upgrade requires someone with a TSO account, proper accesses and authorities. Also, since this type of upgrade is new for Siebel 7.7, you will need to spend time learning how to perform it.