On Wed, 2023-02-15 at 22:08 -0600, Ron wrote:
> On 2/15/23 21:45, Laurenz Albe wrote:
> > On Wed, 2023-02-15 at 10:20 -0600, Ron wrote:
> > > On 2/15/23 02:46, Laurenz Albe wrote:
> > > > Both are the same.
> > > > There is an old myth that says that you should use the more selective
> > > > colum
On 2/15/23 21:45, Laurenz Albe wrote:
On Wed, 2023-02-15 at 10:20 -0600, Ron wrote:
On 2/15/23 02:46, Laurenz Albe wrote:
[snip]
Both are the same.
There is an old myth that says that you should use the more selective column
first
(which would be "code"), but that is just a myth.
Only on Pos
On Wed, 2023-02-15 at 10:20 -0600, Ron wrote:
> On 2/15/23 02:46, Laurenz Albe wrote:
> > Which one is best?
> > > CREATE UNIQUE INDEX ix1 ON art (code, etb)
> > > or
> > > CREATE UNIQUE INDEX ix1 ON art (etb, code)
> > >
> > > (or its PRIMARY KEY equivalent)
> > Both are the same.
> >
> > There
On 2/15/23 02:46, Laurenz Albe wrote:
[snip]
Which one is best?
CREATE UNIQUE INDEX ix1 ON art (code, etb)
or
CREATE UNIQUE INDEX ix1 ON art (etb, code)
(or its PRIMARY KEY equivalent)
Both are the same.
There is an old myth that says that you should use the moew selective column
first
(whic
On Tue, 2023-02-14 at 17:53 +, Sebastien Flaesch wrote:
> When creating an index on multiple columns, does the order of the columns
> matter?
> (I guess so)
It does, but not in your case.
> It's mostly for SELECT statements using a condition that include ALL columns
> of the index (pkey):
>
> On 14/02/2023 18:53 CET Sebastien Flaesch wrote:
>
> Hello!
>
> When creating an index on multiple columns, does the order of the columns
> matter? (I guess so)
Maybe, depending on the queries.
> It's mostly for SELECT statements using a condition that include ALL
> columns of the index (pkey)
Hello!
When creating an index on multiple columns, does the order of the columns
matter?
(I guess so)
It's mostly for SELECT statements using a condition that include ALL columns of
the index (pkey):
SELECT * FROM art WHERE etb='L1' and code='ART345'
I would naturally put the columns wit
