CREATE TABLE word (
	form       text        NOT NULL,
	cat        integer              REFERENCES word (id),
	source     text,
	thumb      text[],
	created    timestamptz          DEFAULT now(),
	id         serial      NOT NULL PRIMARY KEY
);

COMMENT ON COLUMN word.form       IS 'preferred textual representation';
COMMENT ON COLUMN word.cat        IS 'hierarchical classification';
COMMENT ON COLUMN word.source     IS 'URI of downloaded image';
COMMENT ON COLUMN word.thumb      IS 'ImageMagick convert options to create thumbnail from source image';
