On 26-01-16 10:38, Jan-Marc Verlinden wrote:
# Our first version was Java based with a postgres DB, everything stored
as path/values.
Every query would take about a second. We did not even try complex
queries..:-). Also the GUI side did not know what to do with the
pathvalues.
Hi Jan-Marc,
There where some problems handling the path/values, most problems were
based on giving a semantic meaning to the paths.
Storing path and an according a value is very, very quick. I asked
database specialists, and they say this is the best way to go until
billions of records.
Also easy to migrate to another database, for clustering or other reasons.
But there are some problems to solve, which were harder to solve five
years ago.
One problem is the GUI builders, they are looking at a difficult to
understand database-approach, and also easy to create errors in, hard to
debug.
They need JSON to write their datasets in.
The other problem is querying. As long as it are predefined queries, you
can do anything, but then you are no different from an old monolithic
system.
But writing new templates heavily relies on on the fly query building
There are however, some technological progresses, also in the open
source domain.
The path/value storage could come to a better life again with help of
ANTLR, which can help to interpret AQL for this purpose. I even think
this is promising.
Let engineers read the Definitive ANTLR4 Reference by Terence Parr, and
read it with path/values in the back of the mind. Both the GUI problem
as the query problem can be solved.
It should be worth the spent time and the price of the book ;-)
best regards and good luck
Bert Verhees
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