【正文】 。 2023 Global Business Solutions, Inc.Storage Object and Segment Relationship n Create a storage object in tablespacen Tables, indexes, etc. are preallocated to segmentsSegmentExtentSegmentMySegmentBlocksCopyright 169。Copyright 169。 2023 Global Business Solutions, Inc.Temporary Tablesn Store session/ transaction specific datan Show data only to creating sessionn Discard data on mit or preserve data until session endsTablespace A Temp01 Temp02Copyright 169。 2023 Global Business Solutions, Inc.Tips for ReadOnly Tablespacesn Organize by modification requirementsl Frequency of data changel Backup requirementl Security requirementl User requirementn Associated datafile cannot be:l Resized or have auto extend set to onl Renamed to a new datafile name or directoryl OfflineCopyright 169。Define Database ObjectsCopyright 169。 2023 Global Business Solutions, Inc.ReadWrite and ReadOnly Tablespacesn ReadWritel Create, alter, and drop database objectsl Defaultn ReadOnlyl Cannot create or alter database objectsl Can drop certain objectsl Can reside on Worm device or CDROM l Eliminate redundant data backupsl Ideal for Data Warehouse applications and Lookup tablesReadWriteReadOnlyCopyright 169。 2023 Global Business Solutions, Inc.External File SystemLOB Locatorsn LOB data stored separate from nonLOB data n BFILE data stored separate from databaseTablespace A TableName Add… * (Locators point to LOB and BFILE Locations)Tablespace B Copyright 169。 2023 Global Business Solutions, Inc.Function Based Indexn Create on functions or expressionsl User generated PL/SQLl SQL functions (nonaggregate)l External program (C callout)600500300250900660550330275990SALARY * FunctionBasedSingleSQL SELECT salary, salary* FROM employees。 2023 Global Business Solutions, Inc.Tablespace and Datafile RelationshipTablespaceTables, indexes, etc.DatafilesSegmentExtentn A tablespace is created with one or more datafilesn Datafiles are made up of blocksBlocksCopyright 169。 2023 Global Business Solutions, Inc.Read Consistencyn When query executes:l Current time determinedl Blocks with same time readl Newer blocks reconstructed with rollback segmentsCustomers Name Address…1 Acme Inc. 123 Ch2 Zachary’s 1234 Br3 Marie’s 4456 Si4 Chimney 9024 FSELECT * FROM customerUPDATE customer . . .Copyright