ASQLDB is an Array SQL implementation based on HSQLDB and rasdaman. Array SQL is an unofficial extension of standard SQL with advanced query support for multidimensional arrays.
Currently only SELECT queries are supported. An array has to be inserted directly into rasdaman first, and then published in ASQLDB by inserting it's OID in a VARCHAR ARRAY column.
- Configure the rasdaman connection:
editor config.properties - If setting up for the first time, please
mkdir -p /var/hsqldbchown $USER: /var/hsqldb(assuming you run hsqldb with$USER)- Go to the build directory:
cd build, and - Build the jar file:
ant hsqldb - Run the GUI tool:
ant run
Suppose we have a table in ASQLDB:
CREATE TABLE Arrays (
id INTEGER PRIMARY KEY,
acquired DATE,
array VARCHAR(20) ARRAY
);
To publish an array object in collection MYCOLL, with OID = 100, then in Arrays we would insert the following:
INSERT INTO Arrays
VALUES (1, '2014-01-22', ARRAY['MYCOLL:100']);
In SELECT queries then we can do advanced array processing on the array column, and even combine it with other non-array columns, e.g.
SELECT acquired, avg_cells(array[0:100, 50:200]) * id
FROM Arrays
The rasql syntax (http://rasdaman.org/ for more details) is mostly supported as
is, with subtle keyword differences, like ARRAY instead of MARRAY, and
AGGREGATE instead of CONDENSE.
To run ASQLDB specific tests
cd build
ant testselect
Currently around 30% of the tests are failing, SELECT is not fully supported yet.
- Full DML support
- Extend documentation with Array SQL specification and examples
- Adapt JDBC driver for multidimensional array results