The pgExpress Driver PostgreSQL dbExpress Driver installation procedure is similar to any other dbExpress driver's installation.
If you want to install the Delphi version, the files are under the pgExpress installation's
Delphi directory; for the Kylix files, the directory is
Kylix'.
If you're using the installer version (*.exe), it can perform the operations
below for you, except configuring your connections parameters (what you can do manually by editing that file or
just double-clicking a TSQLConnection component). You can edit the default
[PGEConnection] entry it
creates. The steps for manual installation are:
dbexppge.dll (libdbexppge.so on Linux/Kylix)
to a folder in your path. If you are using the multilanguage and/or protocol 3.0 driver, the driver name on the
package will be another, such as dbexpge30-ml.dll or libdbexppge.so.
It's your choice to rename the file or use the corresponding name on the entry on the
dbxconnections(.ini) file.
The usual folder is $Delphi\bin on Windows (where
$Delphi is the Delphi's installed folder), or $kylix/bin on Kylix, but as long as it's on your path, you can
choose any other folder.
libpq.dll (libpq.so on Linux) file from your
PostgreSQL distribution, alongside all it's dependencies into a dir on your PATH. Under
Linux, usually installing the distribution's PostgreSQL or just correlated client libraries will do it.
Check Section 1.1, “Libpq” for more details.
$ProgramFiles\Common Files\Borland Shared\DBExpress
folder depending on your IDE version; please check your documentation on their default location if
you don't find them.
The changes to be applied are the following:
Edit the dbxdrivers.ini file.
On Kylix, this file is called
dbxdrivers. On the [Installed Drivers] section, add the
PostgreSQL=1 key and value:
[Installed Drivers]
DB2=1
Interbase=1
MYSQL=1
Oracle=1
PostgreSQL=1
[PostgreSQL] section:
[Oracle]
GetDriverFunc=getSQLDriverORACLE
LibraryName=dbexpora.dll
VendorLib=OCI.DLL
BlobSize=-1
DataBase=Database Name
ErrorResourceFile=
LocaleCode=0000
Password=password
Oracle TransIsolation=ReadCommited
User_Name=user
[PostgreSQL]
GetDriverFunc=getSQLDriverPOSTGRESQL
LibraryName=dbexppge.dll
VendorLib=LIBPQ.DLL
On Kylix, the PostgreSQL section is slightly different to reflect the Linux
library file names:
[PostgreSQL] GetDriverFunc=getSQLDriverPOSTGRESQL LibraryName=libdbexppge.so VendorLib=libpq.so
Still on Linux/Kylix, you must add your driver's path to the LD_LIBRARY_PATH
environment variable (or copy the driver to your Kylix's bin
subdirectory):
LD_LIBRARY_PATH=/home/steve/lib/export LD_LIBRARY_PATH
Edit the dbxconnections.ini file.
On Kylix, it's is called dbxconnections. This file lists all the dbExpress
connections and it can contain as many entries for the pgExpress Driver as you might want add. We supply
here an example connection, but you should modify it to meet your own settings (specially
the server address, database name, user name and password) params:
[PGEConnection] BlobSize=32 HostName=host Database=database_name DriverName=PostgreSQL Password=temp123 User_Name=steve
The only required parameters are Database,
DriverName,
UserName
and Password if desired. You can use a more
reduced form like the one below (you're encouraged to use it):
[PGEConnection] DriverName=PostgreSQL Database=hostname/database_name User_Name=steve Password=temp123
The other parameters are optional (only those listed above are supported by the pgExpress Driver)
and their meaning is that on dbExpress documentation. Pay special attention to the
Database
parameter. dbExpress only will load the HostName parameter if you set the
TSQLConnection.LoadParamsOnConnectDatabase parameter that avoid that
confusion and also adds support for a Port parameter. It seems like an URL:
host:port/database
Where:
Hostname (DNS or IP) of the machine. If you don't supply
this parameter, it defaults to localhost.
:').
Database = myserver.mydomain.com/database Database = myserver.mydomain.com:5432/database Database = 111.111.111.111:5432/database Database = database
Note that if you supply both the HostName and Database
parameters with embedded hostname (as show above), the Database parameter
will prevail. Don't forget you can add as many sections to the dbxconnections file
as you want, like this:
[PGEConnection] DriverName=PostgreSQL Database=hostname1/database_name User_Name=steve Password=temp123
[pgserver] DriverName=PostgreSQL Database=pgserver/database_name User_Name=john
That's it; the driver should be working now.
dbxdrivers(.ini) and dbxconnections(.ini) files vary from each distribution; for instance, on
Kylix it is ~/.borland, on Delphi6
and 7 it is %CommonFiles%\Borland Shared\DBExpress,
and on BDS 2006 it is %ProgramFiles%\Borland\BDS\4.0\dbExpress.
Please refer to your IDE documentation for the exact location of those configuration files. Also, remember
you can distribute them in the same directory your application is located; that should make distribution
easier.
dbxdrivers(.ini)
and dbxconnections(.ini) for both Delphi and Kylix.
The pgExpress Driver for protocol 3.0 is compatible with Delphi 2007+ which uses the version 4.0 of the dbExpress protocol. We are already in late development of a 4.0 version of our driver, but until there the current version of the driver can be used in compatibility mode by following the these instructions:
Add the following additional strings to the [PostgreSQL] section of dbxdrivers(.ini):
[PostgreSQL] DriverUnit=DBXDynalink DriverPackageLoader=TDBXDynalinkDriverLoader DriverPackage=DBXCommonDriver110.bpl
DBXCommonDriver110.bpl package with your application.
When upgrading to Delphi 2007+, there are some issues that must be observed: