Re: string not equal query, postgresql 9.4.4

On 9/17/2015 6:49 PM, David G. Johnston wrote:
> On Thu, Sep 17, 2015 at 6:18 PM, John Scalia <jayknowsunix(at)gmail(dot)com <mailto:jayknowsunix(at)gmail(dot)com>>wrote:
>
>
> SELECT * FROM results where result <> 'PASS';
>
> and it produced all the rows, not just the ones beginning with visc60 that I expected. Based on what you had written, I should have seen the correct output. So, any ideas?
>
>
> ​ EXPLAIN ANALYZE SELECT * FROM results WHERE result <> 'PASS';
>
> What happens when you run the following? Do you see the same incorrect behavior?
>
> WITH vals (v) AS (
> VALUES ('PASS'::char(4)), ('FAIL'::char(4))
> )
> SELECT
> ​ DISTINCT ​
> *
> FROM vals
> WHERE v <> 'PASS'::char(4);
>
> David J.​
>
I tried your code above, and some additional queries prior to your message arriving, and I see now why I'm still getting multiple row beyond my original expecting. Carefully
looking at the rows being produced showed that each instrument is performing a powerup test and all those passed. I guess I was just expecting too much from distinct and I
understand why. I just need to add a second where clause if I can figure out how to make the powerup test clearly indicated as such in the table.

Thanks for everyone's help, I should have examined the automated data collection more closely.
--
Jay