Thread: sql-porting-problem oracle to postgresql with UPDATE/IS NOT NULL

<p><font face="Arial" size="2">hello list, </font><br /><font face="Arial" size="2">i have some problems with an
sql-statementwhich runs on oracle but not on postgresql (i want update only if result of SELECT is not empty, the
SELECT-queriesare identical):</font><p><font face="Arial" size="2">UPDATE table1 t1<br />         SET (t1.id) =<br />
               (SELECT h.id FROM table2 t2,table3 t3, table1 t1<br />                 WHERE t3.field = t2.field<br />
                       AND t2.id = t1.id<br />                         AND t1.id <> t3.id)<br />         WHERE<br
/>                (SELECT h.id FROM table2 t2,table3 t3, table1 t1<br />                         WHERE t3.field =
t2.field<br/>                                 AND t2.id = t1.id<br />                                 AND t1.id
<>t3.id) IS NOT NULL; </font><br /><br /><p><font face="Arial" size="2">thanks, hans </font><br /><br /> 

On Jul 28, 2009, at 5:58 AM, Gau, Hans-Jürgen wrote:

> hello list,
> i have some problems with an sql-statement which runs on oracle but
> not on postgresql (i want update only if result of SELECT is not
> empty, the SELECT-queries are identical):
>
> UPDATE table1 t1
>         SET (t1.id) =
>                 (SELECT h.id FROM table2 t2,table3 t3, table1 t1
>                 WHERE t3.field = t2.field
>                         AND t2.id = t1.id
>                         AND t1.id <> t3.id)
>         WHERE
>                 (SELECT h.id FROM table2 t2,table3 t3, table1 t1
>                         WHERE t3.field = t2.field
>                                 AND t2.id = t1.id
>                                 AND t1.id <> t3.id) IS NOT NULL;
>
Try this:

UPDATE table1 t1        SET (t1.id) =                (SELECT h.id FROM table2 t2,table3 t3, table1 t1
WHEREt3.field = t2.field                        AND t2.id = t1.id                        AND t1.id <> t3.id)
WHERE           EXISTS (SELECT 1 FROM table2 t2,table3 t3, table1 t1                        WHERE t3.field = t2.field
                            AND t2.id = t1.id                                AND t1.id <> t3.id 
            AND h.id IS NOT NULL);



>
>
> thanks, hans
>
>

--
Daryl
http://itsallsemantics.com

""Everyone thinks of changing the world, but no one thinks of changing
himself."
- Leo Tolstoy

Hello,

Le 28/07/09 14:25, Daryl Richter a écrit :
> 
> On Jul 28, 2009, at 5:58 AM, Gau, Hans-Jürgen wrote:
> 
>> hello list,
>> i have some problems with an sql-statement which runs on oracle but
>> not on postgresql (i want update only if result of SELECT is not
>> empty, the SELECT-queries are identical):
>>
>> UPDATE table1 t1
>>         SET (t1.id) =
>>                 (SELECT h.id FROM table2 t2,table3 t3, table1 t1
>>                 WHERE t3.field = t2.field
>>                         AND t2.id = t1.id
>>                         AND t1.id <> t3.id)
>>         WHERE
>>                 (SELECT h.id FROM table2 t2,table3 t3, table1 t1
>>                         WHERE t3.field = t2.field
>>                                 AND t2.id = t1.id
>>                                 AND t1.id <> t3.id) IS NOT NULL;
>>
> Try this:
> 
> UPDATE table1 t1 [...]
>         WHERE
>             EXISTS (SELECT 1 FROM table2 t2,table3 t3, table1 t1
>                         WHERE t3.field = t2.field
>                                 AND t2.id = t1.id
>                                 AND t1.id <> t3.id
> 
>                 AND h.id IS NOT NULL);
> 

Beyond the solution brought by Daryl Richter, it seems that "h" is an
unbound alias in the original (and also in the suggested) query. Some
clarification would be helpful for further investigation.

Regards.

--
nha / Lyon / France.

On Jul 28, 2009, at 5:10 PM, nha wrote:

> Hello,
>
> Le 28/07/09 14:25, Daryl Richter a écrit :
>>
>> On Jul 28, 2009, at 5:58 AM, Gau, Hans-Jürgen wrote:
>>
>>> hello list,
>>> i have some problems with an sql-statement which runs on oracle but
>>> not on postgresql (i want update only if result of SELECT is not
>>> empty, the SELECT-queries are identical):
>>>
>>> UPDATE table1 t1
>>>        SET (t1.id) =
>>>                (SELECT h.id FROM table2 t2,table3 t3, table1 t1
>>>                WHERE t3.field = t2.field
>>>                        AND t2.id = t1.id
>>>                        AND t1.id <> t3.id)
>>>        WHERE
>>>                (SELECT h.id FROM table2 t2,table3 t3, table1 t1
>>>                        WHERE t3.field = t2.field
>>>                                AND t2.id = t1.id
>>>                                AND t1.id <> t3.id) IS NOT NULL;
>>>
>> Try this:
>>
>> UPDATE table1 t1 [...]
>>        WHERE
>>            EXISTS (SELECT 1 FROM table2 t2,table3 t3, table1 t1
>>                        WHERE t3.field = t2.field
>>                                AND t2.id = t1.id
>>                                AND t1.id <> t3.id
>>
>>                AND h.id IS NOT NULL);
>>
>
> Beyond the solution brought by Daryl Richter, it seems that "h" is an
> unbound alias in the original (and also in the suggested) query. Some
> clarification would be helpful for further investigation.

Ahh, you're right.  I didn't even notice that, just reformatted the
OPs query.

>
> Regards.
>
> --
> nha / Lyon / France.
>
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--
Daryl