Which of the following best describes how the FILTER clause differs from a WHERE clause in aggregation?

easy📝 Conceptual Q2 of 15

PostgreSQL - Aggregate Functions and GROUP BY

Which of the following best describes how the FILTER clause differs from a WHERE clause in aggregation?

AFILTER filters rows before grouping, WHERE filters after grouping

BFILTER is used only for sorting results

CFILTER and WHERE do the same thing in aggregation

DFILTER applies conditions after grouping, WHERE applies before grouping

Step-by-Step Solution

Solution:

Step 1: Understand WHERE and FILTER timing
WHERE filters rows before grouping happens, so it affects which rows enter the aggregation. FILTER applies conditions inside aggregate functions after grouping.
Step 2: Eliminate incorrect options
FILTER does not filter before grouping, and it is not for sorting. WHERE and FILTER are not the same.
Final Answer:
FILTER applies conditions after grouping, WHERE applies before grouping -> Option D
Quick Check:
FILTER vs WHERE timing = FILTER after grouping [OK]

Quick Trick: WHERE filters rows before grouping; FILTER filters inside aggregates [OK]

Common Mistakes:

Master "Aggregate Functions and GROUP BY" in PostgreSQL

9 interactive learning modes - each teaches the same concept differently

Want More Practice?

15+ quiz questions · All difficulty levels · Free