I am typing the below code and it is returning me “ORA-00923: FROM keyword not found where expected”. What is happening?
SELECT max(alias.id) AS "id", (SELECT alias.name FROM EXAM WHERE alias.id = alias.id ) AS "REF", alias.name FROM EXAM alias GROUP BY alias.name ORDER BY alias.name ASC;
Here’s a fiddle: http://sqlfiddle.com/#!4/537e2/1
Below are the methods you can try. The first solution is probably the best. Try others if the first one doesn’t work. Senior developers aren’t just copying/pasting – they read the methods carefully & apply them wisely to each case.
'COLUMN PREFIX' is a scalar string, not a valid (alias) column name. Oracle (flagship, not MySQL) uses Double Quotes for such object names. (The
ORA error indicates you are using the flagship product)
Oracle does not distinguish between
''. anything compared to
NULL is unknown. Your
case statement will always go to the
I don’t think Oracle allows you to use a column alias in the
group by clause. I can’t test right now.
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