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Author Topic: Brainstorming: providing SQLQuery for TDbf  (Read 2841 times)

tatamata

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Brainstorming: providing SQLQuery for TDbf
« on: February 07, 2008, 11:11:02 am »
The obvious frustrating limitation of TDbf component is lack of SQL. It is not problem for simple data-aware applications but is a great problem if you need complicated datasets queried from several tables.
What are your ideas for starting point in implementing SQLQuery component for working with TDbf datasets?
Utilization of existing SQLQuery components?

Regards,

Zlatko

tatamata

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Brainstorming: providing SQLQuery for TDbf
« Reply #1 on: February 12, 2008, 11:55:24 am »
In fact, what I am looking for, seems to be similar to TxQuery component that exists for Delphi. It is commercial though.
A component that would provide SQL querying capabilities for different datasets, such as Memds, Dbf, Sdf etc.
It seems to me that starting point could be JanSQL engine. But it deals with SQL strings, string lists, not TDataset descendants. Also, it is typeless, everything treating as Variant (performance issue?).
The good thing is that it has SQL Tokenizer and complete SQL engine.
So, either rewrite jansql completely, or extend it to transform resultset to TDataset? If the letter one, tranformation should be done twice- first for input datasets, then for resultset.
The component itself could be Memds descendant?

Your opinions?