KwickClips Databases and SQL · 36 sec · free
Where do aggregates belong?
Short answer. In HAVING, not WHERE.
Which runs first?
WHERE, before grouping.
WHERE vs HAVING
| WHERE | HAVING | |
|---|---|---|
| Filters | rows | groups |
| Runs | before group | after group |
| Aggregate? | no | yes |
Remember
| WHERE: rows, no aggregates |
| HAVING: groups, aggregates OK |
Why does where count star give an error? Where filters rows, before grouping. Having filters groups, after grouping. Only having allows aggregates. Where filters rows. Having filters groups.
This clip is from the full lesson: GROUP BY and HAVING — 6 minutes, with the tables, the quick answers and the whole lesson in text.
Useful for: CBSE Class 12 Computer Science (083), CBSE Class 12 Informatics Practices (065), CBSE Class 12 Information Technology (802)
More KwickClips from this lesson
What does GROUP BY do first?36 sec
How many rows does GROUP BY return?36 sec
How many rows remain after HAVING COUNT(*) > 1?36 secVoice-over is AI-generated; the script is written and checked by Kajal Ma'am. Confirm anything you plan around against your official board document. We never ask for a password or an OTP.