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I created 2 tables which contains some relation data. This two tables are joined with LEFT JOIN statement with Core Lab's "MyQuerry" component and DataSource , DbGrid included in Delphi 7. Fields are displaying correctly, but I'm wordering how to update second table, which contains ID relation with first table. I just wanted to update fields directly on dbGrid, but of course nothing happens in tables. Which property MyQuerry or DBGrid or maybe DataSource should I use to update fields in second table linked with LEFT JOIN.
Thank you very, very much.

Try to assign the name of the second table to the MyQuery.UpdatingTable property. You can find the information about this property in the MyDAC help.

Antaeus wrote:Try to assign the name of the second table to the MyQuery.UpdatingTable property. You can find the information about this property in the MyDAC help.

Let me explain it - my code:

MyQuerry1.SQL:='select first_table.first_field, first_table.second_field, second_table.first_field from first_table left join second_table on first_table.id = second_table.first_table_id';


As we know how works "left join".: this SQL will display all records from first_table even second_table contains empty fields.

While UpdatingTable is selected od "second_table" MyDac displaying message 0 fields updated. It's happen because second_table is totally empty. It doesn't contain any data, just structure. I would like to fill second_table with data from first_table and from user with dbgrid.

I'll try to do something with master, detail. If somebody has some hints - thanks very much.

Solution with Master/Detail relationship should be better than a single query with the JOIN clause. Please see the MasterDetail demo of MyDAC. You can find this demo in %MyDAC%\Demos\MasterDetail directory.
%MyDac% is the MyDAC installation path on your computer.