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Libgda BDB interfacing example
==============================
Description:
------------
This example illustrates the GdaDataModelBdb data model object,
part of libgda as of versions >= 3.2.
The GdaDataModelBdb object operates on a single Berkeley DB file and
allows reading and writing on that file. A Berkeley DB database (stored in
a single file) basically stores (key,data) pairs; however the BDB library itself
has no knowledge of the composition of the key and data parts which can be as
complex as programmers can make them.
In this example, the key and data (value) parts of the BDB database are described in the
common.h file:
typedef struct {
char color[COLORSIZE];
int type;
} Key;
typedef struct {
float size;
char name[NAMESIZE];
} Value;
fill.c:
-------
This program creates a small 'access.db' DBD database file and populates
its contents with a few entries. It does not use Libgda at all but only the
BDB library.
access-raw.c:
-------------
This program creates a GdaDataModelBdb object which is by default composed of two
binary columns, and accesses the contents of the key and data binary fields by casting
the binary data to the Key and Value structures mentioned above.
access-custom.c:
----------------
This program subclasses the GdaDataModelBdb object to access the data using 4 columns
(color, type, size and name). The subclassed data model is implemented in
the custom-bdb-model.c and custom-bdb-model.h files.
Compiling and running:
----------------------
To compile (make sure Libgda is installed prior to this):
> make
and to run:
> ./fill
> ./access-raw
> ./access-custom
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