DROP TABLE IF EXISTS datas;
DROP TABLE IF EXISTS refs;
CREATE TABLE refs (
id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT
,ref_type STRING NOT NULL DEFAULT 'H'
,refcount INTEGER NOT NULL DEFAULT 1
,classname STRING
);
CREATE TABLE datas (
id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT
,ref_id INTEGER NOT NULL
,data_type STRING DEFAULT 'S'
,`key` STRING NOT NULL
,value STRING
,FOREIGN KEY (ref_id) REFERENCES refs (id)
ON DELETE CASCADE ON UPDATE CASCADE
,UNIQUE (ref_id, `key` )
);