이연정

[연정]

Table students{

  idx bigint [pk, increment]

  studentID int [not null, unique]

  name varchar(20) [not null]

  department1 varchar(30) [not null]

  department2 varchar(30) [not null]

  gender bool [not null]

  colleage_idx bigint [ref: > colleage.idx]

}

Table subject{

  idx bigint [pk, increment]

  code varchar(10) [not null, unique]

}

Table grade{

  idx bigint [pk, increment]

  score varchar(5) [not null]

 // students_idx bigint [not null]

 // subject_idx bigint [not null]

  students_subject_reg_idx bigint [ref:> students_subject_reg.idx]

}

Table colleage{

  idx bigint [pk, increment]

  coll_name varchar(30) [not null, unique]

}

Table students_subject_reg {

  idx bigint [pk, increment]

  students_idx bigint [ref:> students.idx]

  subject_idx bigint [ref:> subject.idx]

}

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