SQL Query Order of execution

SQL Query Order of execution
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As per my understanding, the order of processing is
1. The FROM/WHERE clause goes first.
2. ROWNUM is assigned and incremented to each output row from the FROM/WHERE clause.
3. GROUP BY is applied.
4. HAVING is applied.
5. SELECT is applied.
6. Distinct is Applied
7. ORDER BY is applied.



SQL Statement
Parsing:- 
Syntax Check
Semantic Chek
Execution:- 
FROM Clause
Where Clause
GROUP By Clause
HAVING clause
SELECT
DISTINCT 
ORDER BY

1. syntax check - 
Are all keywords present OR Not Like "select" , "from" , 

2. semantic check against the dictionary - Are all table names spelt correctly, etc.



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