1.1 Preliminaries SQL is an ANSI/ISO standard lyric for querying and manipulating relational data. Designed to be a human readable language comprising: Data definition facilities Database musical passage operations similarityal algebra operations Aggregation operations It is well-to-do to express simple queries precise tricky to express simplest queries! 1.2 SQL: history SQL was developed at IBM (San Jose Lab) during the 1970s, and standardised during the 1980s. The contemporary standard use by commercial systems is SQL2 (SQL-92). Most systems expound the standard language in various dialects. A revolutionary standard (SQL3) is imminent, to handle the language with objects. It appears that SQL (in some form) will depart the rise of object-relational database systems 1.3 A shirk database: ER schema |[pic] | |Who drinks what? | Â 1.
4 A take on database: relational schema |Drinkers (name, addr, phone) | |Beers (name, manf) | |Bars (name, addr, license, openDate) | |Likes (drinker, beer) | |Sells (bar, beer, price) | |Frequents (drinker, ! bar) | The following notations apply: firsthand keys, extraneous keys and primary keys which are also foreign keys 1.5 Relation Values Bars | charge |Addr |License |openDate | |Australia Hotel |The Rocks |123456 |12/1/1940 | |Coogee Bay Hotel |Coogee |966500 |31/8/1980 | |Lord Nelson |The Rocks |123888 |11/11/1920 | |Marble Bar |Sydney |122123 |1/4/2001 | |Regent Hotel |Kingsford...If you need to get a expert essay, order it on our website:
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