Re: mysql_fdw trouble

On Fri, Oct 30, 2015 at 10:57 AM, Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com>
wrote:

> On 10/30/2015 07:21 AM, Dane Foster wrote:
>
>>
>> On Fri, Oct 30, 2015 at 9:40 AM, Adrian Klaver
>> <adrian(dot)klaver(at)aklaver(dot)com <mailto:adrian(dot)klaver(at)aklaver(dot)com>> wrote:
>>
>> On 10/29/2015 05:38 PM, Dane Foster wrote:
>>
>> Hello,
>>
>> I think I've tripped over another mysq_fdw bug. I've filed a bug
>> report
>> on github already but just in case the problem is w/ my query I
>> figured
>> I would post it here in case someone sees something obvious.
>>
>> The error message I get is: null value in column "location"
>> violates
>> not-null constraint.
>>
>> The DDL is here:
>> https://github.com/EnterpriseDB/mysql_fdw/issues/71
>>
>> For the record I know top posting is a crime against god and
>> humanity
>> but I feel justified because this post is not directly related
>> to the
>> original. So there! Granted it's in the same milieu; and yes this
>> current sentence exists for the sole purpose of me being able to
>> use the
>> word milieu because the opportunity to use it is so few and far
>> between.
>>
>> ​INSERT INTO series (cid, day, title, description, location,
>> duration,
>> can_join)
>> SELECT
>> cid,
>> row_number() OVER (PARTITION BY cid ORDER BY
>> lower(duration)),
>> title,
>> description,
>> location,
>> duration,
>> can_join
>> FROM (
>> SELECT
>> cid,
>> title,
>> description,
>> can_join::BOOLEAN,
>> (SELECT label FROM _locations WHERE loc=location) AS
>> location,
>> ('[' || starts || ', ' || (starts + INTERVAL '4 HOUR') ||
>> ']')::TSZ_PERIOD AS duration
>> FROM
>> _series
>> ) AS v​
>>
>> ​Regards,​
>>
>>
>> So what do you get when you do?:
>>
>> SELECT
>> cid,
>> title,
>> description,
>> can_join::BOOLEAN,
>> (SELECT label FROM _locations WHERE loc=location) AS location,
>> ('[' || starts || ', ' || (starts + INTERVAL '4 HOUR') ||
>> ']')::TSTZRANGE AS duration
>> FROM
>> _series
>> );
>>
>>
>> Dane
>>
>>
>>
>>
>> --
>> Adrian Klaver
>> adrian(dot)klaver(at)aklaver(dot)com <mailto:adrian(dot)klaver(at)aklaver(dot)com>
>>
>> ​
>> I get rows of data, location and all.
>>
>
> And when you do?:
>
> SELECT
> cid,
> row_number() OVER (PARTITION BY cid ORDER BY lower(duration)),
> title,
> description,
> location,
> duration,
> can_join
> FROM (
> SELECT
> cid,
> title,
> description,
> can_join::BOOLEAN,
> (SELECT label FROM _locations WHERE loc=location) AS location,
> ('[' || starts || ', ' || (starts + INTERVAL '4 HOUR') ||
> ']')::TSTZRANGE AS duration
> FROM
> _series
> ) AS v
>
>
>
>> Dane
>> ​
>>
>>
>
> --
> Adrian Klaver
> adrian(dot)klaver(at)aklaver(dot)com
>

​Before I answer your second query question I need to revise my response to
the first. Yes the first query runs w/o an error message but the bit about
"rows and all" was not entirely correct. Out of 313 rows only the first row
had a location. The other 312 rows have NULL in the location column which
is not supposed to happen. To verify this I changed the table names and
removed the PostgreSQL transformations (i.e., use of || and :: for casting)
and ran the query against the MySQL database; it returned 313 rows of data,
location and all.

Now that I've cleared that up.

Your second query also runs w/o any error messages but like the first only
the first row has a non NULL value in the location column.

Dane
​