keywords FIRST / LAST // COM licensing

[Ruslan Zasukhin]

On 8/26/06 8:43 PM, "fellerd at cox.net" <fellerd at cox.net> wrote:

Hi Douglas,

>>> We use the FIRST or LAST functions with string type fields.
>> 
>> Hmm, they are not in SQL92 standard I believe.
>> So sounds like you talk about some non-standard extension of SQL
> 
>> Hmm, you know, as far as I see in this case MIN = FIRST, MAX = LAST.
>> Because group is sorted. Your FIRST command returns MIN in group. You see?
> 
> That maybe, just bringing to your attention that Oracle (big boy) & MSAccess
> (small boy) both use them. So if the smallest and the biggest use them, the
> there must be a use for FIRST and LAST.

Yes interesting. Then I will need read Oracle docs to see why they have
FIRST/LAST. Should be some more reasons then except of string values.

> But I just found of why we use FIRST AND LAST vs. MIN AND MAX on string
> fields. MSAccess only allows Text fields to be dimed up to 255. If you need
> more than 255 characters then you must declare the field type as a Memo
> (unlimited chars) field.

Note, Valentina have:

    String - fixed size field, up to 64K

    VarChar - var size field, up to 2044 chars of UTF-16

    Text - unlimited
 
> Well are most important field in our quoting sys is this memo field, coz
> values can be greater than 255 chars. I just did a test on the crosstab with
> MIN and MAX on the Text field (255 chars or less) and the query worked. But
> MIN and MAX do not work with the Memo field. The FIRST AND LAST functions do
> work like MIN AND MAX on Memo fields.

Hmm, I not remember if our Min/Max work on TEXT fields. It is obvious that
not many sense here if only value itself is not like a single word...

What MAX size of coz? May be with Valentina you will be able use
VarChar[2044] for this ?
 
> Hence, MIN AND MAX work in MSAccess but only up to 255 chars. Then you have
> to use their FIRST AND LAST function to get the same result. But, since
> Valentina allows up to 65,000+ chars on a String or VARCHAR this should be
> more than enough for us to use your MIN and MAX functions instead of FIRST
> and LAST. I still think there is need for FIRST and LAST functions, but that
> can go on the back burner for now.

Aha, okay. Note, in Valentina 2.3 we have limit VarChar to 4K strings. More
than enough for most cases.
 
> I did see all the IF() and DATE() functions on WIKI help. Thanks for
> bringing the search engine in it to my attention. Never used it before. But
> it works like a charm.

------------ 
> I really have been looking for a database to replace MSAccess for 5 years
> already. The only db that I thought might do it was MySql. But I played
> around with it on several different occasions and just could not get past
> the extra config to get going with it. I played around with several
> interfaces and didn't like them also. It just didn't workout for us.
> 
> Valentina is looking better and better every day this week. I have really
> moved Valentina to the top of our list. I still need to find time to work
> with our db now. 

I am glad to hear this.

> I don't know how the RECID and OID fields and binary
> linking will work with how we do things here. I would really love to take
> advantage of their speed.

I recommend to read few articles in our WIKI. On the next page find please
like "Articles".

http://www.valentina-db.com/dokuwiki/doku.php?id=paradigma:public:en:documen
tation:documentation

> I still need to look at examples of how to add records to a table and link
> them to their parent record. I have always used the Foreign key method to
> attach a child to a parent.

> SO I don't quite know how much different it is with your db. I'm hoping
> Valentina is it. I'm really geting tired after five years now of trying to
> find a replacement for MSAccess.
 
Note, we position Valentina as Object-Relational database. This means that
we claim that ANY feature present in Relational Model should work in
Valentina plus MORE.

So you can use simply Foreign Key for this like do any RDBMS,
ObjectPtr is 99% the same in use. It is easy.

Also note, we have ConvertRDB feature to convert ForeignKey-link to
ObjectPtr-link. We need yet develop more such refactoring features for
comfort of developers.

I recommend to read this section of WIKI about links. It explains our points
of views on FK and why we add new types of links, and +/- of each link type.

http://www.valentina-db.com/dokuwiki/doku.php?id=paradigma:public:en:documen
tation:vkernel:vlink:vlink


> I still think the Crosstab/Pivot query would be a plus to have with
> Valentina. The support has been outstanding so far. Thanks Ruslan for giving
> so much attention to our needs. First class operation so far.

We will implement it, do not worry.
We listen Valentina users very carefully.

-- 
Best regards,

Ruslan Zasukhin
VP Engineering and New Technology
Paradigma Software, Inc

Valentina - Joining Worlds of Information
http://www.paradigmasoft.com

[I feel the need: the need for speed]