Difference between truncate delete Ddl dml commands Primary key unique key defination difference Composite key Foreign key Code to link two tables Sql-foreign key Print name and marks of stu with max marks Oops Abstraction interface diff with example Overloading overridding with example Class object with example

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The question covers various topics related to database management, SQL, and object-oriented programming concepts.

Truncate is a DDL command used to delete all records from a table, while delete is a DML command used to remove specific records.
Primary key uniquely identifies each record in a table, while a unique key ensures that all values in a column are unique.
Composite key is a combination of multiple columns that uniquely identify a record in a table.
Foreign key establishes a relationship between two tables by referencing the primary key of another table.
SQL code to link two tables involves using a foreign key constraint in the CREATE TABLE statement.
To print the name and marks of a student with the maximum marks, you can use a SQL query with the MAX() function.
Abstraction in OOP hides complex implementation details, while an interface defines a contract for classes to implement.
Overloading allows multiple methods with the same name but different parameters, while overriding involves redefining a method in a subclass.
A class is a blueprint for creating objects, which are instances of the class.