----- Original Message ----- From: "a.j. welmers" <[EMAIL PROTECTED]>
> --- In [email protected], "David Bolton" <[EMAIL PROTECTED]> wrote: > "Reliability and robustness. Its all OO either way but if you write a > lot of code at the form level its more of a hack than if you write > bespoke classes. Its less important if you have one query, but if > you're working with multiple tables, are you going to reuse the same > query component ............... > David Bolton" > > David can you make me some code snippets or a small application > available, that I can study to understand better what you mentioned. I > am still in the Delphi 5 + using out of the box components [dbgris + > dbnavigator ] and like to go in the direction you mentioned. > thank you > jan welmers This is an example using DAC for Mysql. It has hardcoded values (which is naughty) against a database testdb, though easy enough to making them properties. I'd typically use it as a member of a class. David Use it like this. In the class fladb : tladb; ,,, fladb.select('your sql query'); if fladb.count >0 then begin fladb.query.first; while not fladb.query.eof do begin ... fladb.query.next; end; fladb. unit dacdb; interface uses mySQLDbTables,Db, classes; Type TLaDb = class private FDataBase : TMySqldatabase; FDB : TMysqlQuery; FLastError : string; function GetCount: integer; public Constructor Create; Destructor Destroy;override; function Select(SQL : string ) : integer; function Exec(sql : string) : boolean; property Query : TMySqlQuery read FDB; property LastError : string read FLastError write FLastError; property Count : integer read GetCount; end; implementation uses Sysutils; { TLADb } constructor TLADb.Create; begin { Connected = True DatabaseName = 'database' UserName = 'root' UserPassword = 'xys' Host = 'localhost' ConnectOptions = [] Params.Strings = ( 'Port=3306' 'TIMEOUT=30' 'DatabaseName=testdb' 'UID=root' 'PWD=xys' 'Host=localhost') } FDatabase := TMySqlDatabase.Create(nil); FDatabase.Host := 'localhost'; FDatabase.UserName := 'root'; FDatabase.UserPassword := 'xys'; FDatabase.DatabaseName := 'testdb'; FDatabase.Port := 3306; FDatabase.Connected := True; Fdb := TMySqlQuery.Create(nil); Fdb.Database := FDatabase; end; destructor TLADb.Destroy; begin FDb.Free; FDatabase.Free; end; function TLADb.Exec(sql: string): boolean; begin Fdb.Active := false; Fdb.Sql.Text := SQL; try Fdb.ExecSql; FLastError := ''; result := true; except on E : Exception do begin Result := False; FLastError := E.Message; end; end; end; function TLADb.Select(SQL: string): integer; begin Fdb.Active := false; Fdb.Sql.Text := SQL; try Fdb.Open; FLastError := ''; result := Fdb.RecordCount; except on E : Exception do begin Result := 0; FLastError := E.Message; end; end; end; function TLaDb.GetCount: integer; begin result := fdb.RecordCount; end; end. ------------------------ Yahoo! Groups Sponsor --------------------~--> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/i7folB/TM --------------------------------------------------------------------~-> ----------------------------------------------------- Home page: http://groups.yahoo.com/group/delphi-en/ To unsubscribe: [EMAIL PROTECTED] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/delphi-en/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
