[Solved] Find the mistake in this query:SELECT employee, salary, ROW_NUMBER() OVER w FROM employees WINDOW w AS (PARTITION BY department ORDER salary DESC) | PostgreSQL

PostgreSQL - Window Functions in PostgreSQL

Find the mistake in this query:

SELECT employee, salary, ROW_NUMBER() OVER w
FROM employees
WINDOW w AS (PARTITION BY department ORDER salary DESC)

AMissing BY keyword after ORDER

BROW_NUMBER() cannot be used with named windows

CWINDOW clause must not include PARTITION BY

DORDER BY cannot be combined with PARTITION BY

Step-by-Step Solution

Solution:

Step 1: Review WINDOW clause syntax
ORDER must be followed by BY keyword: ORDER BY salary DESC.
Step 2: Check other parts
ROW_NUMBER() works with named windows; PARTITION BY and ORDER BY can be combined.
Final Answer:
Missing BY keyword after ORDER -> Option A
Quick Check:
ORDER BY required, not just ORDER [OK]

Quick Trick: Use ORDER BY, not ORDER alone in WINDOW clause [OK]

Common Mistakes:

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