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CATE TABLE and how it compares withDELETE: sometimes faster, sometimes not,and why.Chapter 6: FetchingA chapter six is a chapter a PowerBuilderdeveloper should read since it talks about theDECLARE, OPEN, FETCH, and CLOSE statementsas they apply to cursors using SELECTqueries and procedure calls. It also describesthe cursor FOR loop, which vastly simplifies thecursor loops in SQL by eliminating the need toDECLARE all those local variables or code thoseendless FETCH lists. Something a PowerBuilderdeveloper doesn’t do very often because of thedatawindow and datastore we have.Chapter 7: SynchronizingHere you have it – the MobiLink chapter. Itdiscusses how the MobiLink server workstogether with the MobiLink client for ASA tosynchronize data back and forth between aconsolidated database and dozens or thousandsof remote databases. MobiLink scriptsare classified by level (connection, session,table, and row) and by direction (upload versusdownload). And error handling on theserver and client sides is described. This is aninteresting chapter for every serious Pocket-Builder developer. I can highly recommend itif you want to synchronize your mobile devicewith a desktop machine.Chapter 8: PackagingThis chapter is about moving applicationlogic into the database using BEGIN blocksand SQL modules based on BEGIN blocks:procedures, functions, triggers, and events.The SET assignment statement is described,as well as the flow-of-control structures IF,CASE, and WHILE, the EXECUTE IMMEDI-ATE statement, and the connection-levelCREATE VARIABLE statement. This sectionintroduces the basics of exception handling, atopic expanded on in Chapter 9.Chapter 9: ProtectingChapter 9 is the second-longest chapter inthe book. It explores a wide variety of topicsincluding options, transactions, exceptions,errors, subtransactions, locks, blocks, isolationlevels, deadlocks, mutexes, user IDs, privileges,user groups, logging, recovery, backup,restore, and (gasp!) database validation. Manyof these topics are only loosely connected toone another, but they all fall under the generalheading “Crashing, Bashing, Thrashing, andProtection Therefrom.”Breck Carter is an experienced databasedeveloper. He first worked with a relationaldatabase in 1973 (the year I was born) beforethere were any practical commercial implementations.Over the years he has worked as anindependent consultant to develop enterprisedatabases and applications using IMS DB/DC,DB2, Oracle, SQL Server, ASE, and, beginning in1995, SQL Anywhere.Breck has been a member of Team Sybasesince 1993, which means you can find himanswering questions on the SQL Anywherenewsgroups on behalf of Sybase and iAnywhereSolutions. He is also a member of the iAnywhereSolutions Customer Advisory Board, helpingto shape future product direction.Chapter 10: TuningThis chapter might be the one with thebiggest audience since everyone’s interestedin speed, speed, speed. This chapter shouldbe read last because the first rule of optimizationis “Don’t do it.” If you’re an expert, Rule 2also applies: “Don’t do it yet.”Chapter 10 explains the four big performancetuning tools that SQL Anywhere provides:request-level logging, the Index Consultant,the Execution Profiler, and the GraphicalPlan. It then moves on to more arcane topicssuch as file, table, and index fragmentation,and table, index, and database reorganization.Sections on the syntax of CREATE INDEXand database performance counters areincluded, and the book ends with a performancetuning “Tips and Techniques” sectionthat lists 36 do’s and don’ts that didn’t find ahome earlier in the book.ConclusionThe book is easy to read and containsimportant details about SQL Anywhere development.If you’re new to SQL Anywhere thematerial will save you hours of time and dramaticallyshorten your learning curve. Thisbook is simply a must-have for SQL Anywheredatabase developers because it’s a completeand compact reference for experienced developersas well as comprehensive immersion forbeginners and less experienced coders. It’s writtenby someone who has a great deal of experienceusing SQL Anywhere Studio to build realworldsoftware solutions. Have fun reading it.bhamboeck@pocketpb.com32 PBDJ volume12 issue4www.SYS-CON.COM/pbdj/