A brief history of data and databases Spanning

+ A brief history of data and databases Spanning thousands and thousands of years Unattributed pictures from University of Rochester History Site

+ Housekeeping n HW 3 – Grading contract – due before class on Tuesday n Teams – Tuesday n n Some have indicated that they prefer to work alone. See me if you feel strongly and come prepared with a reason why. Project – A couple of people had ideas for alternate projects. n Lewis n Hull n See me after class

+ References for this talk n University of Rochester History Site n http: //quickbase. intuit. com/articles/timeline-of-database-history n http: //www. computerhistory. org/revolution/memorystorage/8/265/2207 - Video

+ Record Keeping – How long? Source: http: //www. ancientscripts. com/cuneiform. html picture – wikipedia 4 th millenium

+ Record Keeping – How long? 3100 BC pictures of goods and then cuniform symbols. Source: http: //www. ancientscripts. com/cuneiform. html picture – wikipedia 4 th millenium

+ Why? n We use records to measure “stuff”. n And most of these records are not digital.

+ Jacquard Loom

Marriage book, Rochester, NY, chronological filing of marriage licenses. From ancestry. com (1790 census, Pittsford, NY)

+ Other non-electronic records n SS cards – 35 million hand typed between 1937 -1938 n Motor vehicle licenses and registrations n Financial records for companies n School records

+ Card Catalogs – An ingeneous indexing system

+ • It didn’t indicate whether the book was available, just where it should be found. (example cards) • Creating the cards required the expertise of librarians.

+ Problem – The 1890 census n Enter Herman Hollerith.

+ Hollerith’s device pantograph Hollerith card Integrating machine

+ First computers The program, the data, the JCL – all done with punchcards

+ Electronic files – Early computing 1950 s – 1970 s

+ Enter the database – Early 1960 s • Objects in a database can be related to one another. • Hierarchical – One record leads to the related record. (Like a tree) • Network – Allowed for multiple relationships (like a network) • The databases used pointers to relate one record to another.

+ Charles Bachman Integrated data store – Dow Chemical CASE products (Computer Aided Engineering)

+ Some issues n While an improvement over file based systems, n these systems required knowledge of the structures to use them. No built in search mechanism. n Very few users understood the structures, access limited to an elite few. n Queries were complex. Took time to get new information and expensive programmer time to produce.

+ Enter the relational DBMS 1970, Edgar Codd Relational DBMS • Mathematician at IBM • Based on Relational Calculus and set theory U of Michigam • Micro. DBMS IBM • System R • First implementation of SQL Led to • Oracle • IBM DB 2 • Informix • Sybase • MS SQL Server (based on Sybase)

+ Relational Ideas n Data is represented as a series of tables. n The tables are Related to one another through a series of keys and foreign keys. n A standard language is used to define the database (DDL) and to query the database (DML). n Tables within the database contain the data about the database (meta data).

+ Why relational? n It is easy for most people to “see” and “get it”. n Makes the data accessible for a wider number of users through user friendly query tools. n Through good database design, space usage is efficient (although this has become less of an issue of late).

+ Codd’s 12 Rules n See notes.

+ The Future? • Object Oriented Databases – Combine data and operations on those data – Allows for inheritance – Oracle (Object-Relational Database) – Postgre(open source object-relational DBMS) – • http: //www. postgresql. org/about/ XML and XML DBMS – XML designed to transport and store data initially envisioned as moving data across the web (w 3 schools. com) – XML Database Management System manages that data

+ Next up – modeling data and relational DBMS terms n A few words about data models. n Activity – Let’s look again at the “ugly” database.