V4RB 2.0 b18 - uploaded

[Ruslan Zasukhin]

On 10/9/04 10:22 AM, "olivier" <vidal_olivier at yahoo.fr> wrote:

>>     This feature continue improvement of non-SQL API of V4RB.
>> 
> 
>>     Union( t1 as Table, t2 as Table ) as Table
>>     Interset( t1 as Table, t2 as Table ) as Table
>>     Difference( t1 as Table, t2 as Table ) as Table
>> 
>> As you see this functions mirror the basic Relational Algebra
>> operations,
>> But again we will be able do this without SQL.
>> 
> 
> 
> What real advantages will bring methods which are not SQL ?
> 
> The advantages really have to be important if we go away from standards
> SQL.

Good question!

    Yes SQL is standard.
    YES SQL is perfect for REMOTE database access and control.

But in the world exists other tasks also,
And SQL sometimes is not the best way.


--------------------------
I think in the first turn THE LOCAL db is an issue.

* SQL is slower because you need spend time to build strings,
    then must exists parser which parse strings,
    which build trees of nodes, which at last of end do call
    the same API function.

* SQL parser and engine usually need to have powerful analysator and
optimizer which also eat space and time

* Or look on this. You have table, you have some WHEHRE condition which
select from million records e.g. 10,000 records.
You sort it by f1.

Now user ask to sort by f2. What you do in SQL way ?
You must again execute the full SQL query, i.e. You again need
        PARSER, optimize, do SEARCH WHERE and only now do new ORDER BY
        Ah, also cursor need unlock records,
        and later again lock records, actually THE SAME records!

What we have with sets?
You have execute search and get set.
Now you can THIS SET sort many times in different ways.
I.e. When user say SORT BY f2, you do only the final step

        sort( s2, f2 )

Cool?  I think very cool!



--------------------------
* another example. SQL92 absolutely is not able handle recursive queries.

    SQL99 have add some features for this, but they are so complex and ugly,
    that it is even hard to understand them.

Instead API methods allow you do work in very natural way.



-- 
Best regards,
Ruslan Zasukhin      [ I feel the need...the need for speed ]
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e-mail: ruslan at paradigmasoft.com
web: http://www.paradigmasoft.com

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