UNIT 3: SQL

History IBM Sequel language developed as part of System R project at the IBM San Jose Research Laboratory Renamed Structured Query Language (SQL) ANSI and ISO standard SQL: SQL-86 SQL-89 SQL-92 SQL:1999 (language name became Y2K compliant!) SQL:2003 Commercial systems offer most, if not all, SQL-92 features, plus varying feature sets from later standards and […]

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unit 5 Relational database design

Relational model Relational Model represents how data is stored in Relational Databases.  A relational database stores data in the form of relations (tables). Consider a relation STUDENT with attributes ROLL_NO, NAME, ADDRESS, PHONE and AGE shown in Table. STUDENT ROLL_NO NAME ADDRESS PHONE AGE 1 Ram Dharan 9455123451 18 2 Ramesh Gorkha 9652431543 18 3 […]

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