book

Expert PL/SQL Practices for Oracle Developers and DBAs

by John Beresniewicz, Adrian Billington, Martin Büchi, Melanie Caffrey, Ron Crisco, Lewis Cunningham, Dominic Delmolino, Sue Harper, Torben Holm, Connor McDonald, Arup Nanda, Stephan Petit, Michael Rosenblum, Robyn Sands, Riyaj Shamsudeen

July 2011

Intermediate to advanced

516 pages

14h 50m

English

Apress

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Row-by-Row ProcessingNested Row-by-Row ProcessingLookup QueriesExcessive Access to DUALExcessive Function CallsDatabase Link CallsExcessive Use of TriggersExcessive CommitsExcessive ParsingSummary
The HeroSample of Dynamic ThinkingSecurity IssuesPerformance and Resource UtilizationObject DependenciesSummary
Why Parallel Processing?Laws Affecting Parallel ProcessingThe Rise of Big DataParallel vs. Distributed ProcessingParallel Hardware ArchitecturesIdentify Your GoalsCandidate Workloads for Parallel ProcessingThe MapReduce Programming ModelBefore Looking to PL/SQLProcesses Available for Parallel ActivitiesUsing Parallel Execution Servers for MapReduceSummary
PL/SQL WarningsConditional CompilationSummary

Why Test Your Code?What Is Unit Testing?Tools for Building Unit TestsPreparing and Maintaining the Unit Test EnvironmentBuilding Unit TestsBroadening the Scope of the TestsSupporting Unit Test FeaturesRunning Tests from the Command LineSummary
The Hardware StoreSetting for the Examples in this ChapterBulk Operations in PL/SQLBulk BindingError Handling with Bulk BindA Justification for Massive CollectionsThe Real Benefit: Client Bulk ProcessingSummary
What This Chapter Will (and Will Not) CoverAutomated Code AnalysisWhen to Analyze?Performing Static AnalysisPerforming Dynamic AnalysisSummary
Design by ContractImplementing PL/SQL ContractsExample: Testing Odd and Even IntegersUseful Contract PatternsPrinciples For Bug-Free CodeSummary
The Cost of Using PL/SQL Functions in SQLReducing the Cost of PL/SQL FunctionsSummary
Explicit CursorsImplicit CursorsStatic REF CursorsDynamic REF CursorsSummary
The Database as PL/SQL-Based Application ServerRequirements of Programming in the LargeUniformity through ConventionsModularization of Code and DataObject-Oriented Programming with PL/SQLMemory ManagementSummary
Lessons from Two Decades of System DevelopmentThe Database and Agile DevelopmentEvolutionary Data ModelingRefactoring the DatabaseCreating an Access Layer via PL/SQLThe Agile ManifestoUsing PL/SQL with Evolutionary Data ModelingSummary
What Is Performance?What Is Profiling?InstrumentationProblem DiagnosisSummary
Why coding conventions?FormattingDynamic CodePackagesStored ProceduresFunctionsError HandlingSummary
Dependency ChainsShortening Dependency ChainsDatatype ReferenceView for Table AlterationsAdding Components into PackagesSynonyms in Dependency ChainsResource LockingForcing Dependency in TriggersCreating Triggers Disabled InitiallySummary

Content preview from Expert PL/SQL Practices for Oracle Developers and DBAs

C H A P T E R 8

Contract-Oriented Programming

by John Beresniewicz

This chapter will introduce you to a powerful software engineering paradigm called Design by Contract and a method for applying it to PL/SQL programming.

Design by Contract

The following quote struck me as a revelation of software-truth when I first read it sometime in the year 2000:

Design by Contract is a powerful metaphor that…makes it possible to design software systems of much higher reliability than ever before; the key is understanding that reliability problems (more commonly known as bugs) largely occur at module boundaries, and most often result from inconsistencies in both sides’ expectations. Design by Contract promotes a much more systematic approach to this issue ...