query/Todo.md

1.3 KiB

Todo

  • Add is_valid() method to connection & connection_impl
  • Read in entity fields
  • Add special handling for update in backends
  • Add ODBC/SQL Server backend

Fetch eager strategies

ONE TO ONE/MANY person address

  • has one address - belongs to person

=> join "address" on "person.id" == "address.person_id"

address person

  • belongs to person - has one address

=> join "person" on "address.person_id" == "person.id"

book author

  • belongs to author - has many books

  • => join "author" on "book.author_id" == "author.id"

HAS MANY TO ONE (WITHOUT RELATION TABLE)

author book

  • has many books - belongs to author

  • => join "book" on "author.id" == "book.author_id"

if "has many" type has primary key & field "author_id" if table name belongs to entity template type?

HAS MANY TO MANY (WITHOUT RELATION TABLE)

student student_course course

  • has many courses - belongs to student - belongs to course - has many students

=> join "student_course" on "student.id" == "student_course.student_id" join "student_course" on "course.id" == "student_course.course_id"

if has many type hasn't primary key (is relation table)