-- -- BOX -- -- -- box logic -- o -- 3 o--|X -- | o| -- 2 +-+-+ | -- | | | | -- 1 | o-+-o -- | | -- 0 +---+ -- -- 0 1 2 3 -- -- boxes are specified by two points, given by four floats x1,y1,x2,y2 CREATE TABLE BOX_TBL (f1 box); INSERT INTO BOX_TBL (f1) VALUES ('(2.0,2.0,0.0,0.0)'); INSERT INTO BOX_TBL (f1) VALUES ('(1.0,1.0,3.0,3.0)'); -- degenerate cases where the box is a line or a point -- note that lines and points boxes all have zero area INSERT INTO BOX_TBL (f1) VALUES ('(2.5, 2.5, 2.5,3.5)'); INSERT INTO BOX_TBL (f1) VALUES ('(3.0, 3.0,3.0,3.0)'); -- badly formatted box inputs INSERT INTO BOX_TBL (f1) VALUES ('(2.3, 4.5)'); ERROR: Bad box external representation '(2.3, 4.5)' INSERT INTO BOX_TBL (f1) VALUES ('asdfasdf(ad'); ERROR: Bad box external representation 'asdfasdf(ad' SELECT '' AS four, BOX_TBL.*; four | f1 ------+--------------------- | (2,2),(0,0) | (3,3),(1,1) | (2.5,3.5),(2.5,2.5) | (3,3),(3,3) (4 rows) SELECT '' AS four, b.*, area(b.f1) as barea FROM BOX_TBL b; four | f1 | barea ------+---------------------+------- | (2,2),(0,0) | 4 | (3,3),(1,1) | 4 | (2.5,3.5),(2.5,2.5) | 0 | (3,3),(3,3) | 0 (4 rows) -- overlap SELECT '' AS three, b.f1 FROM BOX_TBL b WHERE b.f1 && box '(2.5,2.5,1.0,1.0)'; three | f1 -------+--------------------- | (2,2),(0,0) | (3,3),(1,1) | (2.5,3.5),(2.5,2.5) (3 rows) -- left-or-overlap (x only) SELECT '' AS two, b1.* FROM BOX_TBL b1 WHERE b1.f1 &< box '(2.0,2.0,2.5,2.5)'; two | f1 -----+--------------------- | (2,2),(0,0) | (2.5,3.5),(2.5,2.5) (2 rows) -- right-or-overlap (x only) SELECT '' AS two, b1.* FROM BOX_TBL b1 WHERE b1.f1 &> box '(2.0,2.0,2.5,2.5)'; two | f1 -----+--------------------- | (2.5,3.5),(2.5,2.5) | (3,3),(3,3) (2 rows) -- left of SELECT '' AS two, b.f1 FROM BOX_TBL b WHERE b.f1 << box '(3.0,3.0,5.0,5.0)'; two | f1 -----+--------------------- | (2,2),(0,0) | (2.5,3.5),(2.5,2.5) (2 rows) -- area <= SELECT '' AS four, b.f1 FROM BOX_TBL b WHERE b.f1 <= box '(3.0,3.0,5.0,5.0)'; four | f1 ------+--------------------- | (2,2),(0,0) | (3,3),(1,1) | (2.5,3.5),(2.5,2.5) | (3,3),(3,3) (4 rows) -- area < SELECT '' AS two, b.f1 FROM BOX_TBL b WHERE b.f1 < box '(3.0,3.0,5.0,5.0)'; two | f1 -----+--------------------- | (2.5,3.5),(2.5,2.5) | (3,3),(3,3) (2 rows) -- area = SELECT '' AS two, b.f1 FROM BOX_TBL b WHERE b.f1 = box '(3.0,3.0,5.0,5.0)'; two | f1 -----+------------- | (2,2),(0,0) | (3,3),(1,1) (2 rows) -- area > SELECT '' AS two, b.f1 FROM BOX_TBL b -- zero area WHERE b.f1 > box '(3.5,3.0,4.5,3.0)'; two | f1 -----+------------- | (2,2),(0,0) | (3,3),(1,1) (2 rows) -- area >= SELECT '' AS four, b.f1 FROM BOX_TBL b -- zero area WHERE b.f1 >= box '(3.5,3.0,4.5,3.0)'; four | f1 ------+--------------------- | (2,2),(0,0) | (3,3),(1,1) | (2.5,3.5),(2.5,2.5) | (3,3),(3,3) (4 rows) -- right of SELECT '' AS two, b.f1 FROM BOX_TBL b WHERE box '(3.0,3.0,5.0,5.0)' >> b.f1; two | f1 -----+--------------------- | (2,2),(0,0) | (2.5,3.5),(2.5,2.5) (2 rows) -- contained in SELECT '' AS three, b.f1 FROM BOX_TBL b WHERE b.f1 @ box '(0,0,3,3)'; three | f1 -------+------------- | (2,2),(0,0) | (3,3),(1,1) | (3,3),(3,3) (3 rows) -- contains SELECT '' AS three, b.f1 FROM BOX_TBL b WHERE box '(0,0,3,3)' ~ b.f1; three | f1 -------+------------- | (2,2),(0,0) | (3,3),(1,1) | (3,3),(3,3) (3 rows) -- box equality SELECT '' AS one, b.f1 FROM BOX_TBL b WHERE box '(1,1,3,3)' ~= b.f1; one | f1 -----+------------- | (3,3),(1,1) (1 row) -- center of box, left unary operator SELECT '' AS four, @@(b1.f1) AS p FROM BOX_TBL b1; four | p ------+--------- | (1,1) | (2,2) | (2.5,3) | (3,3) (4 rows) -- wholly-contained SELECT '' AS one, b1.*, b2.* FROM BOX_TBL b1, BOX_TBL b2 WHERE b1.f1 ~ b2.f1 and not b1.f1 ~= b2.f1; one | f1 | f1 -----+-------------+------------- | (3,3),(1,1) | (3,3),(3,3) (1 row) SELECT '' AS four, height(f1), width(f1) FROM BOX_TBL; four | height | width ------+--------+------- | 2 | 2 | 2 | 2 | 1 | 0 | 0 | 0 (4 rows)