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Classification of DBMSs Based on the data model used: Traditional: Relational, Network, Hierarchical. Emerging: Object-oriented, Object-relational. Other classifications: Single-user (typically used with micro- computers) vs. multi-user (most DBMSs). Centralized (uses a single computer with one database) vs. distributed (uses multiple compute...

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Cost-estimation-based optimization If the cost of every execution plan can be estimated accurately, then the optimal plan can be eventually found. Two difficulties with cost-estimation based optimization:  There may be too many possible execution plans to enumerate.  It may be difficult to estimate the cost of each execution plan accurately. ...

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Updating tuples in a nested table: update table (select beers from manfs m where m.name = ‘Anheuser’) b set b.color = ‘blue’; First, you have to flatten the object table using the pseudo function table before you can do an update on the object table. Not quite obvious, because update essentially refers only to the object table beers and not ...

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Research Directions (2006-2010) (cont.) Advanced Information Systems: E-/M-Commerce SOA-Based Modern Information Systems Large Database Systems Web Information Systems Modern Information Retrieval Systems Stream Data Management* Bioinformatics*

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Summary Introduction to Database Security Issues Types of Security Threats to databases Database Security and DBA Access Protection, User Accounts, and Database Audits Discretionary Access Control Types of Discretionary Privileges Specifying Privileges Using Views Revoking Privileges Propagation of Privileges Using the GRANT OPTION An ex...

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Additional Query Tuning Guidelines WHERE conditions may be rewritten to utilize the indexes on multiple columns. Example: SELECT REGION#, PROD_TYPE, MONTH, SALES FROM SALES_STATISTICS WHERE REGION# = 3 AND ((PRODUCT_TYPE BETWEEN 1 AND 3) OR (PRODUCT_TYPE BETWEEN 8 AND 10)); may use an index only on REGION# and search through all leaf pa...

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Data Storage Disk Storage Devices Files of Records Operations on Files Unordered Files Ordered Files Hashed Files RAID Technology Indexing Structures for Files Types of Single-level Ordered Indexes Multilevel Indexes Dynamic Multilevel Indexes Using B-Trees and B+-Trees Indexes on Multiple Keys

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Introduction: “goodness” measures for relations Functional dependencies (FDs) Definition of FD Direct, indirect, partial dependencies Inference Rules for FDs Equivalence of Sets of FDs Minimal Sets of FDs Normalization 1NF and dependency problems 2NF – solves partial dependency 3NF – solves indirect dependency BCNF – well-normalized rela...

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SQL developments: an overview SQL DDL: Create, Alter, Drop DML: select, insert, update, delete Introduction to advanced DDL (assertions & triggers), views, DCL (commit, rollback, grant, revoke)

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Brief Introduction to Relational Calculus Another variation of relational calculus called the domain relational calculus, or simply, domain calculus is equivalent to tuple calculus and to relational algebra QBE (Query-By-Example): see Appendix D Domain calculus differs from tuple calculus in the type of variables used in formulas: rather than ha...

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