We discussed the separation between Graphic User Interface (GUI), Business Logic (BL) and Data Access Layer (DAL) – which includes the Data Access Object (DAO). We explored the table relationship flavors 1:1 , 1:many , many:many. we created two SQLite tables containing 1:1 relationship using Primary Key (PK) and Foreign Key (FK) references. then we wrote a C# program which executes a join query on these two tables, and stored the result in an anonymous object (for a new view)
More topics covered:
- Join select query in C#
- Creation of anonymous object from an SQL result
- Combining PK + FK between two tables (SQLite)
- Creating SQLite table with FK null chicken-egg dilemma
Links:
- SQL – 1:1 1:N N:M relationship link
- class code: SQL query for 1:1 tables
- class code: C# SQL for 1:1 join
- Previous homework solution – DAO include Etgar
- Lesson Summary Video!
- Homework!
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