SQL Query: What is the output of below query

WITH T AS (SELECT * FROM A),

T1 AS (SELECT b.* FROM B JOIN T ON b.id = t.id),

T2 AS (SELECT c.* FROM C JOIN T1 ON t1.id = c.id)

SELECT * FROM T2;

 

1.      Explain the purpose of each Common Table Expression (CTE) in the query.

2.      What is the final result of the query, and how does it relate to the tables a, b, and c?

3.      If table a has 100 rows, table b has 50 rows, and table c has 30 rows, what can you infer about the number of rows returned by the final SELECT statement? Assume there are matching IDs in the joins.

4.      How would the query change if you wanted to select only specific columns from t2 instead of all columns?

Test scenarios:

A	B	C	Output
Data	No Data	No Data
	Data Available, But No Matched Record	No Data
		Matched Data with B
		No Matched Data with B
	Matched Data	No Data
		Matched Data with B
		No Matched Data with B
No Data	No Data	No Data
	Data Available	No Data
		Matched Data with B
		No Matched Data with B