Dotnet WebAPI's > Relationships, and answer the following questions

What is the difference between a primary key and a foreign key?

• Primary key - unique in a table and identifies the row
• Foreign Key - when a primary key use referenced in another table.

What is an Alias?

An alias is a way in which you can rename a property in an output.

Demonstrate how you would query a join statement that would get all of a doctors patients from the following collections:

CREATE TABLE doctors (
  id INT NOT NULL AUTO_INCREMENT,
  -- CODE OMITTED
  PRIMARY KEY (id)
)

CREATE TABLE patients (
  id INT NOT NULL AUTO_INCREMENT,
  -- CODE OMITTED
  PRIMARY KEY (id)
)

CREATE TABLE doctors (
  id INT NOT NULL AUTO_INCREMENT,
  doctorId INT NOT NULL,
  patientId INT NOT NULL,

  FOREIGN KEY (doctorId)
    REFERENCES doctors(id),
  FOREIGN KEY (patientId)
    REFERENCES patients(id),
)

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