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SISTEM BASIS DATA 2 NAMA : YULISTIANI NPM : 20311103 MODEL KONSEPTUAL DATABASE   DATA MODEL Data model adalah sekumpulan konsep yang digunakan untuk menjelaskan struktur dari basis data (database structure) dan memberikan gambaran tingkat-tingkat abstraksi data (data abstraction). Data abstraction adalah deskripsi mengenai struktur basis data yang mudah dimengerti oleh user, atau bisa juga mencakup detil dari penyimpanan data yang biasanya perlu diketahui oleh perancang basis data. Database structure mencakup data type (type nama adalah string), relationship (customer berelasi dengan account), dan constraint (ada batasan bahwa tidak bisa menjamin bahwa - peserta MIK harus sudah mengambil KP1).       ▸ Data model:   ▸ Object-based logical model  ▸ Entity-relationship model  ▸ Object-oriented model  ▸ Semantic model  ▸ Fungsional model:       ▸ Record-based logical model:      ▸ Relationship model   ...

Intermediate SQL Join Expressions  A) Views  B) Transactions  C) Integrity Constraints D) SQL Data Types and Schemas  E) Authorization Joined Relations 1) Join operations take two relations and return as a result another relation 2)It also specifies the attributes that are present in the result of the join.  3)The join operations are typically used as subquery expressions in the from clause.   Joined Operation  - Example  1.Relation course 2.Relation prereq  3.Observe that prereq information is missing for CS-315 and course information is missing for CS-437. Outer Join -An extension of the join operation that avoids loss of information -Uses null values.  Left Outer Join Course natural left outer join prereq Right Outer Join  course natural right outer join prereq  Joined Relation  Join operations take two relations and return as a result another relation This person should see a relation described, in SQL, by select ID, n...