Manfred Koizar wrote:
> On Tue, 19 Jul 2005 11:51:51 +0100, Richard Huxton
> wrote:
>
>>You could get away with one query if you converted them to left-joins:
>>INSERT INTO ...
>>SELECT * FROM upload LEFT JOIN ... WHERE f3 IS NULL
>>UNION
>>SELECT * FROM upload LEFT JOIN ... WHERE f4 IS NULL
>
>
>
On Tue, 19 Jul 2005 11:51:51 +0100, Richard Huxton
wrote:
>You could get away with one query if you converted them to left-joins:
>INSERT INTO ...
>SELECT * FROM upload LEFT JOIN ... WHERE f3 IS NULL
>UNION
>SELECT * FROM upload LEFT JOIN ... WHERE f4 IS NULL
For the archives: This won't work.
I will use 2 queries. They run within a function fnUpload(), so I'm going to keep it simple.
On 19 Jul 2005, at 12:51, Richard Huxton wrote:
Yves Vindevogel wrote:
>>> So, I must use a function that will check against u1 and u2, and then
insert if it is ok.
I know that such a function is way sl
Yves Vindevogel wrote:
>>> So, I must use a function that will check against u1 and u2, and then
insert if it is ok.
I know that such a function is way slower that my insert query.
So - you have a table, called something like "upload" with 20,000 rows
and you'd like to know whether it is safe
BTW: thank you for the idea
Begin forwarded message:
From: Yves Vindevogel <[EMAIL PROTECTED]>
Date: Tue 19 Jul 2005 12:20:34 CEST
To: Richard Huxton
Subject: Re: [PERFORM] Insert performance (OT?)
On 19 Jul 2005, at 11:39, Richard Huxton wrote:
Yves Vindevogel wrote:
Hi,
Suppose I
Yves Vindevogel wrote:
Hi,
Suppose I have a table with 4 fields (f1, f2, f3, f4)
I define 2 unique indexes u1 (f1, f2, f3) and u2 (f1, f2, f4)
I have 3 records
A, B, C, D (this will be inserted)
A, B, C, E (this will pass u2, but not u1, thus not inserted)
A, B, F, D (this will pass u1, but no
nobody ?
On 18 Jul 2005, at 21:29, Yves Vindevogel wrote:
Hi,
Suppose I have a table with 4 fields (f1, f2, f3, f4)
I define 2 unique indexes u1 (f1, f2, f3) and u2 (f1, f2, f4)
I have 3 records
A, B, C, D (this will be inserted)
A, B, C, E (this will pass u2, but not u1, thus not inserted)
A,
Hi,
Suppose I have a table with 4 fields (f1, f2, f3, f4)
I define 2 unique indexes u1 (f1, f2, f3) and u2 (f1, f2, f4)
I have 3 records
A, B, C, D (this will be inserted)
A, B, C, E (this will pass u2, but not u1, thus not inserted)
A, B, F, D (this will pass u1, but not u2, thus not inserted)
