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Alan · Guest

Just wonder can Borland support team describe to me like other new comers
about dbExpress how to make the connection to MySQL successfully.
What should I do if I have the following:
1) D7 Professional with and without update
2) MySQL version 4.0.24 on the same machine
3) Win2K Professional

a) Which libmysql.dll should used?There are different libmysql.dll in the
c:mysqllibopt and c:mysqllibdebug.
b) Put it into winntsystem or winntsystem32 ?
c) If I got third-party components like Zeos which support MySQL 4.1, should
I use their libmysql.dll instead ?
d) For the LibraryName property of TSQLConnection, should I use dbexpmys.dll
or dbexpmysql.dll ?

Thanks

paladin · Guest

"Alan" wrote in message

Alan · Guest

No luck.
I put the libmysql.dll into all directory: c:winnt, c:winntsystem,
c:winntsystem32

All failed. I am frustrated.

I just format my harddisk, install D7 and MySQL 4.0.24 but Delphi dbExpress
sucks.

"paladin" <pal (AT) newsgroups (DOT) com> wrote

Cristian Nicola · Guest

The start with a new technology can be slow sometimes, but do not dispair..
Once you'll get used to it you'll love it Very Happy

In regards to your questions:
a) you should use the normal libmysql.dll (the opt one)
b) you can put it anywhere that is accessible to your executable. You
can/should try a LoadLibrary api to make sure the library is in the path.
You can/should also check the library is the right one (it may be that there
is more than one libmysql.dll in your machine). The latest you could simply
do a search, however i would not recommend it for run-time distribution -
imagine an user which has a windowssystem version 3.23 library and you
overwrite it with 4.1.
c) There are 3 types of db access in delphi at the moment
- TDataset descendants (eg: zeos). They are the "classic" way of db
development, and to be honest it is not my prefered method.
- ODBC/ADO - the microsoft standard way of db development - can be tricky at
times, but due to the standard it can have some advantages over the other
methods
- dbx - the new borland way. it is a thin client, with small footprint. It
is very fast compared to the others, but it can be difficult to grasp the
concepts. I always use it for new development
d) dbexpmysql.dll

In regards to dbx, the idea of a thin client is to have a standard as small
and as fast as possible interface between applications and db-vendor
libraris. As it has been mentioned this has some drawbacks by hiding some of
the vendor specifics (eg interbase events), but over all it provides you
with a very nice way of working with the databases. There is another thing
that you should prolly be aware - the dbx is uni-directional (this means you
cannot connect it directly to a gread) and the results are read-only which
means you cant' edit directly the results. Another thing to be aware of is
that dbx does not provide metadata for the databases/tables/queries/etc
unless it is asked for - which is great as you only get what you need.
There are few vendors of dbx drivers, however due to the lack of
documentation it is difficult to implement a driver. In the previous post i
did sent you the link to 2 alternative mysql dbx drivers vendors, but maybe
i should have commented a bit on each of them:
- CrLab driver is oldest on the market. It has been developed to "fix" the
shortcoming of Borland official driver. however last time when i've checked
there was no metadata support (the driver is not complete). It has support
for internal wire-protocol of mysql (using direct-mysql i think - at least
it was last time i';ve checked), libmysql.dll and libmysqld.dll (embedded
mysql library support). Does not seem to have support for SSL. Can't comment
on support, documentation etc.
- MicroOlap is a younger driver, however is much more complete. Similar to
crlab driver it has 3 drivers in one (wire protocol using direct-mysql,
libmysql and libmysqld), and it also has support for SSL (using open ssl and
an internal ssl implementation). It has a linux version (unofficial) and can
be used in single exe development (eg the driver dll can be embedded
directly into the exe - which means 1 single exe that includes/implements
your functionality-dbxdriver-mysql client)
I had been directly involved in the development of this driver, and this
means shortly it should be dual licensed (GPL open source and commercial). I
do believe that the market needs a complete driver, and i do sincerelly hope
dbx4mysql is going to be it. It is activelly developped, generally the fixes
are done in the same day.

If you have any other questions please do not hesitate to contact me,

Kind regards,
Cristian Nicola

ps forgot to mention direct mysql is
http://www.sourceforge.net/projects/directsql

"Alan" <alantse (AT) exemail (DOT) com.au> wrote