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Re: What's difference between "SELECT COUNT(column_1) new_count" vs. "SELECT COUNT(*) new_count"?
Posted by: Mike M
Date: March 12, 2021 12:49PM

Hi Peter,

I want to count the number of channels (column w.channel) by each group: direct, indirect, others.

I'm told to do this as the solution:
SELECT s.name, w.channel, COUNT(*) num_events

To me, it is doing a rowcount of the entire table. That's not correct! It should be doing "COUNT(w.channel) num_events", because it's asking for w.channel column count. Why involve the entire table into it?

Thanks!

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Written By
Posted
What's difference between "SELECT COUNT(column_1) new_count" vs. "SELECT COUNT(*) new_count"?
Mike M
March 12, 2021 11:22AM
Re: What's difference between "SELECT COUNT(column_1) new_count" vs. "SELECT COUNT(*) new_count"?
Peter Brawley
March 12, 2021 11:54AM
Re: What's difference between "SELECT COUNT(column_1) new_count" vs. "SELECT COUNT(*) new_count"?
Mike M
March 12, 2021 12:49PM
Re: What's difference between "SELECT COUNT(column_1) new_count" vs. "SELECT COUNT(*) new_count"?
Peter Brawley
March 12, 2021 02:47PM


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