TQuery, TTable, TDataSet.
TTable, TDataSource Data Controls TQuery. DataSource TQuery.
TQuery:
- Active - , (true) (false)
- Eof, Bof - true, , .
- DatabaseName - (alias) , .
- DataSource - (.. , ).
- Fields - (run-time only) , .
- Params - , SomeNo :
Select * from Orders where CustNo=:SomeNo
- SQL - , SQL.
, SQL (Structured Query Language), , dBase Paradox. ( , , . " SQL"), . SQL . , , , , . , SQL , , ++ Builder. dBase Paradox SQL Borland Database Engine.
TQuery SQL , , , , .
- RequestLive - true , , . RequestLive false, read-only.
TQuery:
- ExecSQL - SQL-, SQL, . , . SELECT ( ) Open. ExecSQL:
Query1->Close();
Query1->SQL->Clear();
Query1->SQL->Add("Delete emp where empno=1010");
Query1->ExecSQL();
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- Open - TQuery. Active true. , ( SELECT). Open:
Query1->Open();
- Close - TQuery. Close Active false. Close:
Query1->Close();
- Prepare - , SQL, . , Open ExecSQL. Prepare , , Open ExecSQL ( , SQL Monitor). Prepare:
Query1->Close();
Query1->SQL->Add("Delete emp where empno=:empno");
Query1->Prepare();
TQuery , TDataSet. :
- First, Last, Next, Prior , , , :
- MoveBy .
- Insert, Edit, Delete, Append, Post, Cancel - . Insert , :
Query2->Insert();
Query2->Fields[0]->AsInteger = 100;
Query2->Fields[1]->AsString =Edit1->Text;
Query2->Post();
Post Insert, Update Delete, . Cancel Insert, Delete, Edit Append.
- FreeBookmark, GetBookmark, GotoBookmark- - ( ) .
, - Visual Query Builder, SQL TQuery, - .