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rathinagiri wrote:

sudip wrote: I don't know how do you understand exactly what I want?

Because, I had also struggled like you.

sudip wrote:Hi,

I can login to MySql and create database, tables from my HMG program. And it's not a "copy-cat programming", I can write the codes of my own. (not a big deal but something is always better than nothing)

Now, I am analyzing the logic of data-entry screen. I have some points in my mind.
1. Using browse is difficult (if not impossible), so grid should be used for browsing data.
2. Skip, go (xxx) will not work, as records are fetched from server and stored in array.
3. A selective part of the table (I can say subset of table) should be fetched from the table in stead of getting all records in a browse control.
4. Main difference between normal dbf table and RDBMS table is that 1st one is record based and 2nd one is set based.

For the above reasons our general way of xbase programming should be modified when we use sql.

/*
* MINIGUI - Harbour Win32 GUI library Demo
*
* Copyright 2002-2008 Roberto Lopez <harbourminigui@gmail.com>
* http://harbourminigui.googlepages.com/
*
* Copyright 2008 Grigory Filatov <gfilatov@freemail.ru>
*
* Based on RDDSQL sample included in Harbour distribution
*/

#include "minigui.ch"
#include "dbinfo.ch"
#include "error.ch"

#define DBI_QUERY 1001

#define RDDI_CONNECT 1001
#define RDDI_DISCONNECT 1002
#define RDDI_EXECUTE 1003
#define RDDI_ERROR 1004
#define RDDI_ERRORNO 1005
#define RDDI_NEWID 1006
#define RDDI_AFFECTEDROWS 1007
#define RDDI_QUERY 1008

ANNOUNCE RDDSYS
REQUEST MYSQLDD, SQLMIX

*--------------------------------------------------------*
Function Main()
*--------------------------------------------------------*

RDDSETDEFAULT( "SQLMIX" )

IF RDDINFO( RDDI_CONNECT, {"MYSQL", "localhost", "root",, "test"} ) == 0
MsgStop("Unable connect to the server!", "Error")
Return nil
ENDIF

DEFINE WINDOW Form_1 ;
AT 0,0 ;
WIDTH 640 HEIGHT 480 ;
TITLE 'MiniGUI SQL Database Driver Demo' ;
MAIN NOMAXIMIZE ;
ON INIT OpenTable() ;
ON RELEASE CloseTable()

DEFINE MAIN MENU

DEFINE POPUP 'Test'
MENUITEM 'Add record' ACTION AddRecord()
SEPARATOR
ITEM "Exit" ACTION ThisWindow.Release()
END POPUP

END MENU

@ 10,10 BROWSE Browse_1 ;
WIDTH 610 ;
HEIGHT 390 ;
HEADERS { 'Code' , 'Name' , 'Residents' } ;
WIDTHS { 50 , 160 , 100 } ;
WORKAREA country ;
FIELDS { 'country->Code' , 'country->Name' , 'country->Residents' } ;
JUSTIFY { BROWSE_JTFY_LEFT, BROWSE_JTFY_LEFT, BROWSE_JTFY_RIGHT }

END WINDOW

CENTER WINDOW Form_1

ACTIVATE WINDOW Form_1

Return nil

*--------------------------------------------------------*
Procedure OpenTable
*--------------------------------------------------------*

If CreateTable()

DBUSEAREA( .T.,, "SELECT * FROM country", "country" )

INDEX ON FIELD->RESIDENTS TAG residents TO country

GO TOP

Else

ReleaseAllWindows()

EndIf

Return

*--------------------------------------------------------*
Procedure CloseTable
*--------------------------------------------------------*

DBCLOSEALL()

Return

*--------------------------------------------------------*
Procedure AddRecord
*--------------------------------------------------------*

APPEND BLANK

REPLACE CODE WITH 'ARG', ;
NAME WITH 'Argentina', ;
RESIDENTS WITH 38740000

GO TOP
Form_1.Browse_1.Refresh

Return

*--------------------------------------------------------*
Function CreateTable
*--------------------------------------------------------*
Local ret := .T.

RDDINFO(RDDI_EXECUTE, "DROP TABLE country")
If RDDINFO(RDDI_EXECUTE, "CREATE TABLE country (CODE char(3), NAME char(50), RESIDENTS int(11))")
If ! RDDINFO(RDDI_EXECUTE, "INSERT INTO country values ('LTU', 'Lithuania', 3369600), ('USA', 'United States of America', 305397000), ('POR', 'Portugal', 10617600), ('POL', 'Poland', 38115967), ('AUS', 'Australia', 21446187), ('FRA', 'France', 64473140), ('RUS', 'Russia', 141900000)")
MsgStop("Can't fill table Country!", "Error")
ret := .F.
EndIf
Else
MsgStop("Can't create table Country!", "Error")
ret := .F.
EndIf

Return ret

sudip wrote:Hello Grigory,
...
May be I require HbSqlDD. So, from where I can download it and how to use it?

Can you please help me?

sudip wrote:Hi,

I can login to MySql and create database, tables from my HMG program. And it's not a "copy-cat programming", I can write the codes of my own. (not a big deal but something is always better than nothing)

Now, I am analyzing the logic of data-entry screen. I have some points in my mind.
1. Using browse is difficult (if not impossible), so grid should be used for browsing data.
2. Skip, go (xxx) will not work, as records are fetched from server and stored in array.
3. A selective part of the table (I can say subset of table) should be fetched from the table in stead of getting all records in a browse control.
4. Main difference between normal dbf table and RDBMS table is that 1st one is record based and 2nd one is set based.

For the above reasons our general way of xbase programming should be modified when we use sql.

Thank you all for such a wonderful "journey". May be I am slow, because of my daily schedule.

With best regards.

Sudip

gfilatov wrote: You are right for case when you use the class Tmysqlserver.
But we have a contrib library HbSqlDD (SQL Database Driver) in Harbour SVN.
You will use the MySql database with this library by "old fashion" commands for DBF managing.
Take a look for a small sample below:
>...>
I hope that give you an idea

Grigory wrote:
Hello Sudip,

This library is included in HMG Extended Edition distribution.
Take a look for source at the folder minigui\source\HbSqlDD and sample at the folder minigui\samples\Advanced\MySqlDD.

IMHO, the usage of browse, skip is not necessary in RDBMS based programming as you had correctly said, here we deal with a record set.

I'm sure that this library will replace RDDADO and TMySql definitively (at least, I plan to do it for my own applications).
I'm waiting for the next Harbour 'official' release to include in the distribution.

sudip wrote: I have some doubts in my mind.
1. If there any possibility of performance degradation using "browse" with HbSqlDD?
2. Can we use any SQL database with HbSqlDD? If yes, then nothing like it
3. Can we perform BEGIN TRANSACTION .... END TRANSACTION .... with HbSqlDD?

In VFP, there are 2 things called "Remote Views" and "Connections". I had very bad experience regarding skipping and browsing records of large tables with "Remote View", I hope (and I am sure) HbSqlDD will be far far better than "Remote View"