Cross Join for Missing table (Select all and Select or Insert the Missing Row Only) - sql

Question

I have two table and have to fill in a list of missing values in one of the table based on the other one. First table has student's information and the second table has Grade related info, Grade and Grade description.
Table One
ID Name yearWithUs Grade Course Level
1 Jim 2004 4 4
2 Jim 2004 4 1
2 Jim 2003 3 3
4 Jim 2002 2 3
4 Jim 2002 2 1
3 Jim 2001 1 2
3 Jim 2001 1 1
Table two -- logic is.. A Student in a higher Course Level can change to a lower Course Level at anytime during the semester. And It can only go downward 1 level at a time. Example: Jim in his second grade first was assigned to attend course in level 3. He need to attend course in level 2 first before he can attend course in level 1. Means. Row for course level 2 at jim's first grade is missing.
Table Two
ID Grade Grade_Desc Course Level Course Desc
1 1 First Grade 1 Basic
2 1 First Grade 2 Normal
3 1 First Grade 3 Hard
4 1 First Grade 4 Expert
5 2 Second Grade 1
6 2 Second Grade 2
7 2 Second Grade 3
8 2 Second Grade 4
. . .
. . .
. . .
Logic of Table Two
ID Grade Grade_Desc Course Level Possible Move
1 1 First Grade 1 Null
2 1 First Grade 2 1
3 1 First Grade 3 2
4 1 First Grade 4 3
Ouptput one ... how to use select statement to return Jim's Grade?
ID Name Grade_Desc Grade yerWithUs Course Level
1 Jim Fourth Grade 4 2004 4
2 Jim Fourth Grade 4 2004 3
3 Jim Fourth Grade 4 2004 2
4 Jim Fourth Grade 4 2004 1
5 Jim Third Grade 3 2003 3
6 Jim Second Grade 2 2002 3
7 Jim Second Grade 2 2002 2
8 Jim Second Grade 2 2002 1
9 Jim First Grade 2 2001 2
10 Jim First Grade 2 2001 1
Output Two..How to retrieve only the missing row into a new temp table?
ID Name Grade_Desc Grade yearWithUs Course Level
2 Jim Fourth Grade 4 2004 3
3 Jim Fourth Grade 4 2004 2
7 Jim Second Grade 2 2002 2
I am currently is using a messy Cursor Statement to do it. The structure looks really messy and hard to debug return errors. I did a lot of research, and saw people use Cross Join to fill the missing portion which looks really clean (See example below)... I have tried the script it myself in many different way by using the cross join example below...obviously, I failed. I found a similar question in stackoverflow..but I am not able to understand how does it work and why without looking at the data....I need help to understand how to use cross join to rerun missing row? and I am open to any other possible solution.
"SELECT calendar.Date,
Category.Cat,
Score = ISNULL(Scores.Score, 0)
FROM Calendar
CROSS JOIN Catogory
LEFT JOIN Scores
ON Scores.Cat = Category.Cat
AND Scores.Date = Calendar.Date
WHERE Calendar.DayOfMonth = 1;"
Inserting missing rows with a join
Thank You

Answer 1

This will produce that output:
select distinct name, grade, Grade_Desc
from one
cross join two

Answer 2

If select is all you want then:
Select row_number() over(order by (select 1)) as id, * from
(Select distinct name from t1)t1
cross join t2
Here is fiddle http://sqlfiddle.com/#!6/a8a42/3

Answer 3

Try this out:
Create #Temp
DECLARE #Name VARCHAR(100) = 'Jim'
SELECT ROW_NUMBER() OVER (ORDER BY B.Grade DESC,B.CourseLevel DESC) ID,
A.Name,
B.Grade_Desc,
B.Grade,
A.YearWithUs,
B.[Course Level]
INTO #temp
FROM
(
SELECT DISTINCT Name,YearWithUs,Grade
FROM TableOne
WHERE Name = #Name
) A
INNER JOIN TableTwo B
ON A.Grade = B.Grade
Output One
SELECT *
FROM #temp
Output Two into #OutputTwo(temp table)
SELECT A.* INTO #OutputTwo
FROM #temp A
LEFT JOIN TableOne B
ON A.Grade = B.Grade
AND A.[Course Level] = B.[Course Level]
WHERE A.Grade IS NULL AND A.[Course Level] IS NULL