Recap of Mar 4 File Organization Major concepts Files are made up of records records are made up of fields Disk blocks are smaller than files and larger than records files must be split into disk blocks for storage and the records in a file must be grouped somehow for storage on disk blocks independent of the file organization Fixed length records Variable length records Block structure fixed packed or slotted page File structure heap sequential hashed or clustered Details of the above file structures Data Dictionary The data dictionary also called system catalog stores metadata data about data For example Information about relations names of relations names and types of attributes of each relation names and definitions of views integrity constraints User and account information including passwords Data Dictionary Statistical and descriptive data number of tuples in each relation Physical file organization information how relation is stored sequential hash clustered etc physical location of relation operating system file name or disk addresses of blocks containing records of the relation Information about indices about which more after the midterm when we cover chapter 12 Data Dictionary In effect the data dictionary is a mini database The data within can either be stored as special purpose data structures and code to access it or a set of relations using the existing database structures and code to access it most common solution Data Dictionary Example of a possible system catalog representation Relation metadata Attribute metadata type User metadata Index metadata View metadata relation name number of attributes storage organization location attribute name relation name domainposition length user name encrypted password group index name relation name index type index attributes view name definition Reading and Review Upcoming dates Mar 11 HW 2 is due Mar 11 and 13 midterm review Mar 18 midterm Text Sections we ve covered Chapter 1 Introduction Chapter 2 E R data model Chapter 3 except 3 4 3 5 Relational model Chapter 4 SQL Chapter 6 Integrity and Security Chapter 7 up to and including 7 7 Relational Database Design Chapter 11 except 11 3 and 11 9 Storage and File Structure Reading and Review Chapter 1 Introduction 1 1 Applications and motivation 1 2 Database systems vs file systems 1 3 Views 1 4 Data models 1 5 Database languages 1 6 Database users and administrators 1 7 1 10 other stuff 1 11 Summary Reading and Review Chapter 2 Entity Relationship Model 2 1 Basic concepts entities entity sets relationship set s and attributes 2 2 Constraints and mapping 2 3 Keys 2 4 Design issues 2 5 E R Diagram 2 6 Weak entity sets 2 7 Extended E R features specialization aggregation 2 8 Design of an E R schema 2 9 Reduction of an E R schema to tables 2 10 ignore 2 11 Summary Reading and Review Chapter 3 Relational Model 3 1 Structure of relational databases 3 2 The relational algebra 3 3 Extended relational algebra operations 3 4 3 5 ignore 3 6 Tuple relational calculus 3 7 Domain relational calculus 3 8 Summary Reading and Review Chapter 4 SQL 4 1 Background 4 2 Basic structure 4 3 Set operations 4 4 Aggregate functions 4 5 Null values 4 6 Nested subqueries 4 7 4 8 ignore 4 9 Modification of the database 4 10 ignore 4 11 4 14 really ignore 4 15 Summary Reading and Review Chapter 6 Integrity and Security 6 1 Domain Constraints 6 2 Referential Integrity 6 3 Assertions 6 4 Triggers 6 5 Security and Authorization 6 6 6 7 ignore 6 8 Summary Reading and Review Chapter 7 Relational Database Design 7 1 First Normal Form 7 2 Pitfalls in Relational Database Design 7 3 Functional Dependencies 7 4 Decomposition 7 5 Desirable Properties of Decomposition 7 6 BCNF 7 7 Third Normal Form 7 8 7 10 ignore 7 11 Summary Reading and Review Chapter 11 Storage and File Structure 11 1 Overview of physical storage media 11 2 Magnetic Disks 11 3 RAID not responsible for this 11 4 Tertiary Storage 11 5 Storage Access 11 6 File Organization 11 7 Organization of Records in Files 11 8 Data Dictionary Storage 11 9 ignore 11 10 Summary
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