Java Core Class (Type, File)

17. Garbage collector

1. What is GC?

2. Ways to interact with Garbage Collector for a developer.

3. Strong, Soft, Weak, Phantom references. When and how to use, best practice.

4. Finalize method known issues.
SQL
1. Joins (inner, outer…)

1. What is join? Different types of SQL join clauses and how are they used.

2. Differences between inner join and left join.

3. Differences between left join and right join.

4. Full outer join. How to use.

5. Non Equi Join.

6. Self join. When and how to use.

7. Nested join.

8. Cartesian join.

2. Keys (Primary, unique, foreign)

1. What is primary key? Restrictions, best practice.

2. What is unique key? Restrictions, best practice.

3. What is foreign key? Restrictions, best practice.

4. Primary vs unique key.

5. Foreign vs primary key.

3. Indexes

1. What is an index? When and how to create.

2. Advantages and disadvantages of using indexes.