diff --git a/ex101/ex101.1.1/container_files/postgres/hr_depts.sql b/ex101/ex101.1.1/container_files/postgres/hr_depts.sql
index c00c09a..6915f4e 100644
--- a/ex101/ex101.1.1/container_files/postgres/hr_depts.sql
+++ b/ex101/ex101.1.1/container_files/postgres/hr_depts.sql
@@ -1,7 +1,7 @@
 create table hr_depts (
     dept_id         varchar(5) primary key,
     name            varchar(60),
-    parent_dept_id  varchar(5),
+    parent_dept_id  varchar(5) references hr_depts (dept_id),
     abbrev          varchar(5)
 );
 
@@ -121,10 +121,10 @@ insert into hr_depts(dept_id, name, parent_dept_id, abbrev) values
 /************* hr_orgs *************/
 
 create table hr_orgs (
-   dept_id         VARCHAR(5) primary key,
+   dept_id         VARCHAR(5) primary key references hr_depts (dept_id),
    abbrev          VARCHAR(5),
-   min_dept_id     VARCHAR(5),
-   max_dept_id	   VARCHAR(5),
+   min_dept_id     VARCHAR(5) references hr_depts (dept_id),
+   max_dept_id	   VARCHAR(5) references hr_depts (dept_id),
    range_desc      VARCHAR(30)
 );
 
diff --git a/ex101/ex101.1.1/container_files/postgres/hr_jobs.sql b/ex101/ex101.1.1/container_files/postgres/hr_jobs.sql
index ad1ed7b..ac86308 100644
--- a/ex101/ex101.1.1/container_files/postgres/hr_jobs.sql
+++ b/ex101/ex101.1.1/container_files/postgres/hr_jobs.sql
@@ -1,13 +1,11 @@
 /************* hr_positions *************/
 
 create table hr_positions (
-    position_id   varchar(5),
-    dept_id       varchar(5),
+    position_id   varchar(5) primary key,
+    dept_id       varchar(5) references hr_depts (dept_id),
     role          varchar(10)
 );
 
-alter table hr_positions add primary key (position_id);
-
 insert into hr_positions (position_id, dept_id, role) values
 ('10000','10000','staff'),
 ('10001','10000','staff'),
@@ -1520,8 +1518,9 @@ insert into hr_positions (position_id, dept_id, role) values
 /************* hr_jobs *************/
 
 create table hr_jobs (
-    position_id   varchar(5),
-    person_id     varchar(10)
+    position_id   varchar(5) references hr_positions (position_id),
+    person_id     varchar(10),
+    constraint pk_hr_jobs primary key (position_id, person_id)
 );
 
 insert into hr_jobs (position_id, person_id) values
diff --git a/ex101/ex101.1.1/container_files/postgres/sis_courses.sql b/ex101/ex101.1.1/container_files/postgres/sis_courses.sql
index 01e2b61..6343a73 100644
--- a/ex101/ex101.1.1/container_files/postgres/sis_courses.sql
+++ b/ex101/ex101.1.1/container_files/postgres/sis_courses.sql
@@ -2,8 +2,7 @@
 
 create table sis_courses (
     course_id    integer primary key,
-/*    dept_id      varchar(5), */
-    dept_id    varchar(5) references sis_acad_depts (dept_id),
+    dept_id      varchar(5) references sis_acad_depts (dept_id),
     course_num   varchar(5),
     title        varchar(200)
 );
diff --git a/ex101/ex101.1.1/container_files/postgres/sis_enrollment.sql b/ex101/ex101.1.1/container_files/postgres/sis_enrollment.sql
index 315e088..2f069f2 100644
--- a/ex101/ex101.1.1/container_files/postgres/sis_enrollment.sql
+++ b/ex101/ex101.1.1/container_files/postgres/sis_enrollment.sql
@@ -1,7 +1,7 @@
 /************* sis_enrollment *************/
 
 create table sis_enrollment (
-    course_id    integer,
+    course_id    integer references sis_courses (course_id),
     person_id    varchar(10),
     term         varchar(9),
     role         varchar(10),
diff --git a/ex101/ex101.1.1/container_files/postgres/sis_programs.sql b/ex101/ex101.1.1/container_files/postgres/sis_programs.sql
index daec336..823278c 100644
--- a/ex101/ex101.1.1/container_files/postgres/sis_programs.sql
+++ b/ex101/ex101.1.1/container_files/postgres/sis_programs.sql
@@ -130,7 +130,7 @@ create table sis_stu_programs (
     grad_year_expected varchar(10),
     school_id          varchar(10),
     acad_dept_id       varchar(10) references sis_acad_depts (dept_id),
-    prog_status_id     varchar(2),
+    prog_status_id     varchar(2) references sis_prog_status (prog_status_id),
     constraint pk_sis_stu_programs primary key (person_id, program_idx)
 );