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Serialization with tntdb
========================
Tntdb supports the serialization framework of cxxtools. This makes it easy to
write objects into the database and read them back.
Typically applications has business objects, which describes the entities of the
application. When writing serialization and deserialization operators in
cxxtools the objects can be easily converted to various formats and back to
objects, e.g. json or xml. Also they can be easily transfered via rpc to another
process wich may be on a different host.
With the serialization support of tntdb the very same serialization
operators are used to store the objects in the database or read back.
See the demos `serialize.cpp`, `deserialize.cpp` and `csvoutput.cpp` to
see how.
To try the demos, create a database using demodb.sql. The easies way is to use
sqlite:
sqlite3 test.db <demodb.sql
This creates a table `myobjects`. Running `serialize` creates a record in
the table. You need to specify the dburl as parameter to the demo:
./serialize sqlite:test.db
You can verify is using the command:
sqlite3 test.db 'select * from myobjects'
The `deserialize` demo shows, how to extract the data back to the application.
It reads all objects from the myobjects table and outputs the content:
./deserialize sqlite:test.db
This outputs the data of the object to the terminal.
The `csvoutput` demo is a little more generic. It executes a sql statement
passed as the second parameter (the first is again the dburl) and converts the
result to csv, json or xml. Run:
./csvoutput sqlite:test.db 'select * from myobjects'
You see again the content of the myobjects table as a csv file.
Using the switch -j enables json output. Try:
./csvoutput -j sqlite:test.db 'select * from myobjects'
The content is now printed as json.
With the switch -x you can select xml output:
./csvoutput -x sqlite:test.db 'select * from myobjects'
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