postgres/contrib/pageinspect/sql/btree.sql

CREATE TABLE test1 (a int8, b text);
INSERT INTO test1 VALUES (72057594037927937, 'text');
CREATE INDEX test1_a_idx ON test1 USING btree (a);

\x

SELECT * FROM bt_metap('test1_a_idx');

SELECT * FROM bt_page_stats('test1_a_idx', 0);
SELECT * FROM bt_page_stats('test1_a_idx', 1);
SELECT * FROM bt_page_stats('test1_a_idx', 2);

SELECT * FROM bt_page_items('test1_a_idx', 0);
SELECT * FROM bt_page_items('test1_a_idx', 1);
SELECT * FROM bt_page_items('test1_a_idx', 2);

SELECT * FROM bt_page_items(get_raw_page('test1_a_idx', 0));
SELECT * FROM bt_page_items(get_raw_page('test1_a_idx', 1));
SELECT * FROM bt_page_items(get_raw_page('test1_a_idx', 2));

DROP TABLE test1;