【正文】
anced Index Tree (B*Tree)ROOTBRANCHROWIDPOINTERDATASEGMENT0000020234000000020232023249930003001400149995000700090005000599970007200810090009999ROWID|1/4” Rolled Sheet|100 Feet|5 Days|.LEAFCopyright 169。 2023 Global Business Solutions, Inc.Global Partitioned Indexesn Can improve performancen Can contain keys from all partitions of corresponding tableCustomer Sales IndexCustomers AL…INCustomers KS…NY Customers OH…WYCopyright 169。 2023 Global Business Solutions, Inc.Rollback Segment Typesn Privatel Must include segment name in ROLLBACK_SEGMENTS parametern Publicl A pool of rollback segments that may be acquired by any instance mounting databasen Deferredl Created in SYSTEM tablespace when tablespace taken offline and transactions cannot be rolled backCopyright 169。 2023 Global Business Solutions, Inc.Define Database Objects Summaryn Segments are preallocated when objects createdn Segments consist of extentsn Extents are a set of contiguous blocksn As data is added, segments fill upn Storage management is essentialDataSegmentCustomers Name Address…1 Acme Inc. 123 Ch2 Zachary’s 1234 Br3 Marie’s 4456 Si4 Chimney 9024 FCopyright 169。 2023 Global Business Solutions, Inc.Bootstrap Segmentn Contains dictionary definitions loaded on openn Is not user accessiblen Resides in SYSTEM tablespacen Requires no DBA maintenanceBootstrapSegmentRollbackSegmentIndexSegmentBootstrap SegmentCopyright 169。 2023 Global Business Solutions, Inc.Database Segmentsn Set of extents containing specific types of dataBootstrapSegmentTemporarySegmentRollbackSegmentIndexSegmentData SegmentExtentExtentExtentCopyright 169。 2023 Global Business Solutions, Inc.Partition Datan Depose tables and indexesn Each partition can be stored in different tablespaceCustomerCustNo CustName State…1 Kodak NY 4 Oracle CA 5 US Steel PA 6 Quest WA 7 Motorola TX Customers AL…INCustomers KS…NY Customers OH…WYCopyright 169。 2023 Global Business Solutions, Inc.Customers Index Name 1 Acme Inc. 2 Zachary’s 3 Marie’s 4 Chimney Indexesn Optimize queriesl ROWID (Block.Row.File)n Stored independent of tablesn Consume minimal spacen Reduce I/On Index on WHERE clause columnsCustomers Table Name Addre..3 Marie’s 4456 Si 1 Acme Inc. 1236 Ch4 Chimney 9024 F 2 Zachary’s 1234 BrCopyright 169。 2