Left Outer Join course natural left outerjoin prereg course id title dept name credits prereg id BIO-301 Genetics Biology 4 BIO-101 CS-190 Game Design Comp.Sci. 4 CS-101 CS-315 Robotics Comp.Sci. 3 null In relational algebra:course prereq Database System Concepts-7th Edition 4.15 @Silberschatz,Korth and Sudarshan
Database System Concepts - 7 4.15 ©Silberschatz, Korth and Sudarshan th Edition Left Outer Join ▪ course natural left outer join prereq ▪ In relational algebra: course ⟕ prereq
Right Outer Join ■ course natural right outerjoin prereg course id title dept name credits prereg id BIO-301 Genetics Biology 4 BIO-101 CS-190 Game Design Comp.Sci. 4 CS-101 CS-347 null null null CS-101 In relational algebra:course p prereg Database System Concepts-7th Edition 4.16 @Silberschatz,Korth and Sudarshan
Database System Concepts - 7 4.16 ©Silberschatz, Korth and Sudarshan th Edition Right Outer Join ▪ course natural right outer join prereq ▪ In relational algebra: course ⟖ prereq
Full Outer Join course natural full outer join prereg course id title dept name credits prereg id BIO-301 Genetics Biology 4 BIO-101 CS-190 Game Design Comp.Sci. 4 CS-101 CS-315 Robotics Comp.Sci. 3 null CS-347 null null null CS-101 In relational algebra: course∝prereq Database System Concepts-7th Edition 4.17 @Silberschatz,Korth and Sudarshan
Database System Concepts - 7 4.17 ©Silberschatz, Korth and Sudarshan th Edition Full Outer Join ▪ course natural full outer join prereq ▪ In relational algebra: course ⟗ prereq
Joined Types and Conditions Join operations take two relations and return as a result another relation. These additional operations are typically used as subquery expressions in the from clause Join condition-defines which tuples in the two relations match. Join type-defines how tuples in each relation that do not match any tuple in the other relation (based on the join condition)are treated. Join types Join conditions inner join natural left outer join on <predicate> right outer join using (A1 A2,....An) full outer join Database System Concepts-7th Edition 4.18 @Silberschatz,Korth and Sudarshan
Database System Concepts - 7 4.18 ©Silberschatz, Korth and Sudarshan th Edition Joined Types and Conditions ▪ Join operations take two relations and return as a result another relation. ▪ These additional operations are typically used as subquery expressions in the from clause ▪ Join condition – defines which tuples in the two relations match. ▪ Join type – defines how tuples in each relation that do not match any tuple in the other relation (based on the join condition) are treated
Joined Relations-Examples course natural right outerjoin prereq course id title dept name credits prereg id BIO-301 Genetics Biology 4 BIO-101 CS-190 Game Design Comp.Sci. 4 CS-101 CS-347 null null null CS-101 course full outer join prereq using (course_id) course id title dept name credits prereg id BIO-301 Genetics Biology 4 BIO-101 CS-190 Game Design Comp.Sci. 4 CS-101 CS-315 Robotics Comp.Sci. 3 null CS-347 null null null CS-101 Database System Concepts-7th Edition 4.19 @Silberschatz,Korth and Sudarshan
Database System Concepts - 7 4.19 ©Silberschatz, Korth and Sudarshan th Edition Joined Relations – Examples ▪ course natural right outer join prereq ▪ course full outer join prerequsing (course_id)