CREATE EXTENSION tablefunc; -- -- normal_rand() -- no easy way to do this for regression testing -- SELECT avg(normal_rand)::int, count(*) FROM normal_rand(100, 250, 0.2); avg | count -----+------- 250 | 100 (1 row) -- negative number of tuples SELECT avg(normal_rand)::int, count(*) FROM normal_rand(-1, 250, 0.2); ERROR: number of rows cannot be negative -- -- crosstab() -- CREATE TABLE ct(id int, rowclass text, rowid text, attribute text, val text); \copy ct from 'data/ct.data' SELECT * FROM crosstab2('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' and (attribute = ''att2'' or attribute = ''att3'') ORDER BY 1,2;'); row_name | category_1 | category_2 ----------+------------+------------ test1 | val2 | val3 test2 | val6 | val7 | val10 | val11 (3 rows) SELECT * FROM crosstab3('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' and (attribute = ''att2'' or attribute = ''att3'') ORDER BY 1,2;'); row_name | category_1 | category_2 | category_3 ----------+------------+------------+------------ test1 | val2 | val3 | test2 | val6 | val7 | | val10 | val11 | (3 rows) SELECT * FROM crosstab4('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' and (attribute = ''att2'' or attribute = ''att3'') ORDER BY 1,2;'); row_name | category_1 | category_2 | category_3 | category_4 ----------+------------+------------+------------+------------ test1 | val2 | val3 | | test2 | val6 | val7 | | | val10 | val11 | | (3 rows) SELECT * FROM crosstab2('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' ORDER BY 1,2;'); row_name | category_1 | category_2 ----------+------------+------------ test1 | val1 | val2 test2 | val5 | val6 | val9 | val10 (3 rows) SELECT * FROM crosstab3('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' ORDER BY 1,2;'); row_name | category_1 | category_2 | category_3 ----------+------------+------------+------------ test1 | val1 | val2 | val3 test2 | val5 | val6 | val7 | val9 | val10 | val11 (3 rows) SELECT * FROM crosstab4('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' ORDER BY 1,2;'); row_name | category_1 | category_2 | category_3 | category_4 ----------+------------+------------+------------+------------ test1 | val1 | val2 | val3 | val4 test2 | val5 | val6 | val7 | val8 | val9 | val10 | val11 | val12 (3 rows) SELECT * FROM crosstab2('SELECT rowid, attribute, val FROM ct where rowclass = ''group2'' and (attribute = ''att1'' or attribute = ''att2'') ORDER BY 1,2;'); row_name | category_1 | category_2 ----------+------------+------------ test3 | val1 | val2 test4 | val4 | val5 (2 rows) SELECT * FROM crosstab3('SELECT rowid, attribute, val FROM ct where rowclass = ''group2'' and (attribute = ''att1'' or attribute = ''att2'') ORDER BY 1,2;'); row_name | category_1 | category_2 | category_3 ----------+------------+------------+------------ test3 | val1 | val2 | test4 | val4 | val5 | (2 rows) SELECT * FROM crosstab4('SELECT rowid, attribute, val FROM ct where rowclass = ''group2'' and (attribute = ''att1'' or attribute = ''att2'') ORDER BY 1,2;'); row_name | category_1 | category_2 | category_3 | category_4 ----------+------------+------------+------------+------------ test3 | val1 | val2 | | test4 | val4 | val5 | | (2 rows) SELECT * FROM crosstab2('SELECT rowid, attribute, val FROM ct where rowclass = ''group2'' ORDER BY 1,2;'); row_name | category_1 | category_2 ----------+------------+------------ test3 | val1 | val2 test4 | val4 | val5 (2 rows) SELECT * FROM crosstab3('SELECT rowid, attribute, val FROM ct where rowclass = ''group2'' ORDER BY 1,2;'); row_name | category_1 | category_2 | category_3 ----------+------------+------------+------------ test3 | val1 | val2 | val3 test4 | val4 | val5 | val6 (2 rows) SELECT * FROM crosstab4('SELECT rowid, attribute, val FROM ct where rowclass = ''group2'' ORDER BY 1,2;'); row_name | category_1 | category_2 | category_3 | category_4 ----------+------------+------------+------------+------------ test3 | val1 | val2 | val3 | test4 | val4 | val5 | val6 | (2 rows) SELECT * FROM crosstab('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' ORDER BY 1,2;') AS c(rowid text, att1 text, att2 text); rowid | att1 | att2 -------+------+------- test1 | val1 | val2 test2 | val5 | val6 | val9 | val10 (3 rows) SELECT * FROM crosstab('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' ORDER BY 1,2;') AS c(rowid text, att1 text, att2 text, att3 text); rowid | att1 | att2 | att3 -------+------+-------+------- test1 | val1 | val2 | val3 test2 | val5 | val6 | val7 | val9 | val10 | val11 (3 rows) SELECT * FROM crosstab('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' ORDER BY 1,2;') AS c(rowid text, att1 text, att2 text, att3 text, att4 text); rowid | att1 | att2 | att3 | att4 -------+------+-------+-------+------- test1 | val1 | val2 | val3 | val4 test2 | val5 | val6 | val7 | val8 | val9 | val10 | val11 | val12 (3 rows) -- check it works with OUT parameters, too CREATE FUNCTION crosstab_out(text, OUT rowid text, OUT att1 text, OUT att2 text, OUT att3 text) RETURNS setof record AS '$libdir/tablefunc','crosstab' LANGUAGE C STABLE STRICT; SELECT * FROM crosstab_out('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' ORDER BY 1,2;'); rowid | att1 | att2 | att3 -------+------+-------+------- test1 | val1 | val2 | val3 test2 | val5 | val6 | val7 | val9 | val10 | val11 (3 rows) -- check error reporting SELECT * FROM crosstab('SELECT rowid, val FROM ct where rowclass = ''group1'' and (attribute = ''att2'' or attribute = ''att3'') ORDER BY 1,2;') AS ct(row_name text, category_1 text, category_2 text); ERROR: invalid crosstab source data query DETAIL: The query must return 3 columns: row_name, category, and value. SELECT * FROM crosstab('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' and (attribute = ''att2'' or attribute = ''att3'') ORDER BY 1,2;') AS ct(row_name text); ERROR: invalid crosstab return type DETAIL: Return row must have at least two columns. SELECT * FROM crosstab('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' and (attribute = ''att2'' or attribute = ''att3'') ORDER BY 1,2;') AS ct(row_name int, category_1 text, category_2 text); ERROR: invalid crosstab return type DETAIL: Source row_name datatype text does not match return row_name datatype integer. SELECT * FROM crosstab('SELECT rowid, attribute, val FROM ct where rowclass = ''group1'' and (attribute = ''att2'' or attribute = ''att3'') ORDER BY 1,2;') AS ct(row_name text, category_1 text, category_2 int); ERROR: invalid crosstab return type DETAIL: Source value datatype text does not match return value datatype integer in column 3. -- -- hash based crosstab -- create table cth(id serial, rowid text, rowdt timestamp, attribute text, val text); insert into cth values(DEFAULT,'test1','01 March 2003','temperature','42'); insert into cth values(DEFAULT,'test1','01 March 2003','test_result','PASS'); -- the next line is intentionally left commented and is therefore a "missing" attribute -- insert into cth values(DEFAULT,'test1','01 March 2003','test_startdate','28 February 2003'); insert into cth values(DEFAULT,'test1','01 March 2003','volts','2.6987'); insert into cth values(DEFAULT,'test2','02 March 2003','temperature','53'); insert into cth values(DEFAULT,'test2','02 March 2003','test_result','FAIL'); insert into cth values(DEFAULT,'test2','02 March 2003','test_startdate','01 March 2003'); insert into cth values(DEFAULT,'test2','02 March 2003','volts','3.1234'); -- next group tests for NULL rowids insert into cth values(DEFAULT,NULL,'25 October 2007','temperature','57'); insert into cth values(DEFAULT,NULL,'25 October 2007','test_result','PASS'); insert into cth values(DEFAULT,NULL,'25 October 2007','test_startdate','24 October 2007'); insert into cth values(DEFAULT,NULL,'25 October 2007','volts','1.41234'); -- return attributes as plain text SELECT * FROM crosstab( 'SELECT rowid, rowdt, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth ORDER BY 1') AS c(rowid text, rowdt timestamp, temperature text, test_result text, test_startdate text, volts text); rowid | rowdt | temperature | test_result | test_startdate | volts -------+--------------------------+-------------+-------------+-----------------+--------- test1 | Sat Mar 01 00:00:00 2003 | 42 | PASS | | 2.6987 test2 | Sun Mar 02 00:00:00 2003 | 53 | FAIL | 01 March 2003 | 3.1234 | Thu Oct 25 00:00:00 2007 | 57 | PASS | 24 October 2007 | 1.41234 (3 rows) -- this time without rowdt SELECT * FROM crosstab( 'SELECT rowid, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth ORDER BY 1') AS c(rowid text, temperature text, test_result text, test_startdate text, volts text); rowid | temperature | test_result | test_startdate | volts -------+-------------+-------------+-----------------+--------- test1 | 42 | PASS | | 2.6987 test2 | 53 | FAIL | 01 March 2003 | 3.1234 | 57 | PASS | 24 October 2007 | 1.41234 (3 rows) -- convert attributes to specific datatypes SELECT * FROM crosstab( 'SELECT rowid, rowdt, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth ORDER BY 1') AS c(rowid text, rowdt timestamp, temperature int4, test_result text, test_startdate timestamp, volts float8); rowid | rowdt | temperature | test_result | test_startdate | volts -------+--------------------------+-------------+-------------+--------------------------+--------- test1 | Sat Mar 01 00:00:00 2003 | 42 | PASS | | 2.6987 test2 | Sun Mar 02 00:00:00 2003 | 53 | FAIL | Sat Mar 01 00:00:00 2003 | 3.1234 | Thu Oct 25 00:00:00 2007 | 57 | PASS | Wed Oct 24 00:00:00 2007 | 1.41234 (3 rows) -- source query and category query out of sync SELECT * FROM crosstab( 'SELECT rowid, rowdt, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth WHERE attribute IN (''temperature'',''test_result'',''test_startdate'') ORDER BY 1') AS c(rowid text, rowdt timestamp, temperature int4, test_result text, test_startdate timestamp); rowid | rowdt | temperature | test_result | test_startdate -------+--------------------------+-------------+-------------+-------------------------- test1 | Sat Mar 01 00:00:00 2003 | 42 | PASS | test2 | Sun Mar 02 00:00:00 2003 | 53 | FAIL | Sat Mar 01 00:00:00 2003 | Thu Oct 25 00:00:00 2007 | 57 | PASS | Wed Oct 24 00:00:00 2007 (3 rows) -- if category query generates no rows, get expected error SELECT * FROM crosstab( 'SELECT rowid, rowdt, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth WHERE attribute = ''a'' ORDER BY 1') AS c(rowid text, rowdt timestamp, temperature int4, test_result text, test_startdate timestamp, volts float8); ERROR: crosstab categories query must return at least one row -- if category query generates more than one column, get expected error SELECT * FROM crosstab( 'SELECT rowid, rowdt, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT rowdt, attribute FROM cth ORDER BY 2') AS c(rowid text, rowdt timestamp, temperature int4, test_result text, test_startdate timestamp, volts float8); ERROR: invalid crosstab categories query DETAIL: The query must return one column. -- if category query generates a NULL value, get expected error SELECT * FROM crosstab( 'SELECT rowid, rowdt, attribute, val FROM cth ORDER BY 1', 'SELECT NULL::text') AS c(rowid text, rowdt timestamp, temperature int4, test_result text, test_startdate timestamp, volts float8); ERROR: crosstab category value must not be null -- if source query returns zero rows, get zero rows returned SELECT * FROM crosstab( 'SELECT rowid, rowdt, attribute, val FROM cth WHERE false ORDER BY 1', 'SELECT DISTINCT attribute FROM cth ORDER BY 1') AS c(rowid text, rowdt timestamp, temperature text, test_result text, test_startdate text, volts text); rowid | rowdt | temperature | test_result | test_startdate | volts -------+-------+-------------+-------------+----------------+------- (0 rows) -- if source query returns zero rows, get zero rows returned even if category query generates no rows SELECT * FROM crosstab( 'SELECT rowid, rowdt, attribute, val FROM cth WHERE false ORDER BY 1', 'SELECT DISTINCT attribute FROM cth WHERE false ORDER BY 1') AS c(rowid text, rowdt timestamp, temperature text, test_result text, test_startdate text, volts text); rowid | rowdt | temperature | test_result | test_startdate | volts -------+-------+-------------+-------------+----------------+------- (0 rows) -- check errors with inappropriate input rowtype SELECT * FROM crosstab( 'SELECT rowid, attribute FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth ORDER BY 1') AS c(rowid text, temperature text, test_result text, test_startdate text, volts text); ERROR: invalid crosstab source data query DETAIL: The query must return at least 3 columns: row_name, category, and value. SELECT * FROM crosstab( 'SELECT rowid, rowdt, rowdt, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth ORDER BY 1') AS c(rowid text, rowdt timestamp, temperature int4, test_result text, test_startdate timestamp, volts float8); ERROR: invalid crosstab return type DETAIL: Return row must have 7 columns, not 6. -- check errors with inappropriate result rowtype SELECT * FROM crosstab( 'SELECT rowid, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth ORDER BY 1') AS c(rowid text); ERROR: invalid crosstab return type DETAIL: Return row must have at least two columns. -- check it works with a named result rowtype create type my_crosstab_result as ( rowid text, rowdt timestamp, temperature int4, test_result text, test_startdate timestamp, volts float8); CREATE FUNCTION crosstab_named(text, text) RETURNS setof my_crosstab_result AS '$libdir/tablefunc','crosstab_hash' LANGUAGE C STABLE STRICT; SELECT * FROM crosstab_named( 'SELECT rowid, rowdt, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth ORDER BY 1'); rowid | rowdt | temperature | test_result | test_startdate | volts -------+--------------------------+-------------+-------------+--------------------------+--------- test1 | Sat Mar 01 00:00:00 2003 | 42 | PASS | | 2.6987 test2 | Sun Mar 02 00:00:00 2003 | 53 | FAIL | Sat Mar 01 00:00:00 2003 | 3.1234 | Thu Oct 25 00:00:00 2007 | 57 | PASS | Wed Oct 24 00:00:00 2007 | 1.41234 (3 rows) -- check it works with OUT parameters CREATE FUNCTION crosstab_out(text, text, OUT rowid text, OUT rowdt timestamp, OUT temperature int4, OUT test_result text, OUT test_startdate timestamp, OUT volts float8) RETURNS setof record AS '$libdir/tablefunc','crosstab_hash' LANGUAGE C STABLE STRICT; SELECT * FROM crosstab_out( 'SELECT rowid, rowdt, attribute, val FROM cth ORDER BY 1', 'SELECT DISTINCT attribute FROM cth ORDER BY 1'); rowid | rowdt | temperature | test_result | test_startdate | volts -------+--------------------------+-------------+-------------+--------------------------+--------- test1 | Sat Mar 01 00:00:00 2003 | 42 | PASS | | 2.6987 test2 | Sun Mar 02 00:00:00 2003 | 53 | FAIL | Sat Mar 01 00:00:00 2003 | 3.1234 | Thu Oct 25 00:00:00 2007 | 57 | PASS | Wed Oct 24 00:00:00 2007 | 1.41234 (3 rows) -- -- connectby -- -- test connectby with text based hierarchy CREATE TABLE connectby_text(keyid text, parent_keyid text, pos int); \copy connectby_text from 'data/connectby_text.data' -- with branch, without orderby SELECT * FROM connectby('connectby_text', 'keyid', 'parent_keyid', 'row2', 0, '~') AS t(keyid text, parent_keyid text, level int, branch text); keyid | parent_keyid | level | branch -------+--------------+-------+--------------------- row2 | | 0 | row2 row4 | row2 | 1 | row2~row4 row6 | row4 | 2 | row2~row4~row6 row8 | row6 | 3 | row2~row4~row6~row8 row5 | row2 | 1 | row2~row5 row9 | row5 | 2 | row2~row5~row9 (6 rows) -- without branch, without orderby SELECT * FROM connectby('connectby_text', 'keyid', 'parent_keyid', 'row2', 0) AS t(keyid text, parent_keyid text, level int); keyid | parent_keyid | level -------+--------------+------- row2 | | 0 row4 | row2 | 1 row6 | row4 | 2 row8 | row6 | 3 row5 | row2 | 1 row9 | row5 | 2 (6 rows) -- with branch, with orderby SELECT * FROM connectby('connectby_text', 'keyid', 'parent_keyid', 'pos', 'row2', 0, '~') AS t(keyid text, parent_keyid text, level int, branch text, pos int) ORDER BY t.pos; keyid | parent_keyid | level | branch | pos -------+--------------+-------+---------------------+----- row2 | | 0 | row2 | 1 row5 | row2 | 1 | row2~row5 | 2 row9 | row5 | 2 | row2~row5~row9 | 3 row4 | row2 | 1 | row2~row4 | 4 row6 | row4 | 2 | row2~row4~row6 | 5 row8 | row6 | 3 | row2~row4~row6~row8 | 6 (6 rows) -- without branch, with orderby SELECT * FROM connectby('connectby_text', 'keyid', 'parent_keyid', 'pos', 'row2', 0) AS t(keyid text, parent_keyid text, level int, pos int) ORDER BY t.pos; keyid | parent_keyid | level | pos -------+--------------+-------+----- row2 | | 0 | 1 row5 | row2 | 1 | 2 row9 | row5 | 2 | 3 row4 | row2 | 1 | 4 row6 | row4 | 2 | 5 row8 | row6 | 3 | 6 (6 rows) -- test connectby with int based hierarchy CREATE TABLE connectby_int(keyid int, parent_keyid int); \copy connectby_int from 'data/connectby_int.data' -- with branch SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0, '~') AS t(keyid int, parent_keyid int, level int, branch text); keyid | parent_keyid | level | branch -------+--------------+-------+--------- 2 | | 0 | 2 4 | 2 | 1 | 2~4 6 | 4 | 2 | 2~4~6 8 | 6 | 3 | 2~4~6~8 5 | 2 | 1 | 2~5 9 | 5 | 2 | 2~5~9 (6 rows) -- without branch SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0) AS t(keyid int, parent_keyid int, level int); keyid | parent_keyid | level -------+--------------+------- 2 | | 0 4 | 2 | 1 6 | 4 | 2 8 | 6 | 3 5 | 2 | 1 9 | 5 | 2 (6 rows) -- recursion detection INSERT INTO connectby_int VALUES(10,9); INSERT INTO connectby_int VALUES(11,10); INSERT INTO connectby_int VALUES(9,11); -- should fail due to infinite recursion SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0, '~') AS t(keyid int, parent_keyid int, level int, branch text); ERROR: infinite recursion detected -- infinite recursion failure avoided by depth limit SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 4, '~') AS t(keyid int, parent_keyid int, level int, branch text); keyid | parent_keyid | level | branch -------+--------------+-------+------------- 2 | | 0 | 2 4 | 2 | 1 | 2~4 6 | 4 | 2 | 2~4~6 8 | 6 | 3 | 2~4~6~8 5 | 2 | 1 | 2~5 9 | 5 | 2 | 2~5~9 10 | 9 | 3 | 2~5~9~10 11 | 10 | 4 | 2~5~9~10~11 (8 rows) -- should fail as first two columns must have the same type SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0, '~') AS t(keyid text, parent_keyid int, level int, branch text); ERROR: invalid connectby return type DETAIL: Source key type integer does not match return key type text. -- should fail as key field datatype should match return datatype SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0, '~') AS t(keyid float8, parent_keyid float8, level int, branch text); ERROR: invalid connectby return type DETAIL: Source key type integer does not match return key type double precision. SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0, '~') AS t(keyid int, parent_keyid float8, level int, branch text); ERROR: invalid connectby return type DETAIL: Source parent key type integer does not match return parent key type double precision. -- check other rowtype mismatch cases SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0) AS t(keyid int, parent_keyid int, level int, branch text); ERROR: invalid connectby return type DETAIL: Return row must have 3 columns, not 4. SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0, '~') AS t(keyid int, parent_keyid int, level int); ERROR: invalid connectby return type DETAIL: Return row must have 4 columns, not 3. SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0) AS t(keyid int, parent_keyid text, level int); ERROR: invalid connectby return type DETAIL: Source parent key type integer does not match return parent key type text. SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0, '~') AS t(keyid int, parent_keyid int, level float, branch float); ERROR: invalid connectby return type DETAIL: Third return column (depth) must be type integer. SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '2', 0, '~') AS t(keyid int, parent_keyid int, level int, branch float); ERROR: invalid connectby return type DETAIL: Fourth return column (branch) must be type text. SELECT * FROM connectby('connectby_text', 'keyid', 'parent_keyid', 'pos', 'row2', 0, '~') AS t(keyid text, parent_keyid text, level int, branch text, pos text); ERROR: invalid connectby return type DETAIL: Fifth return column (serial) must be type integer. SELECT * FROM connectby('connectby_text', 'keyid', 'parent_keyid', 'pos', 'row2', 0) AS t(keyid text, parent_keyid text, level int, pos text); ERROR: invalid connectby return type DETAIL: Fourth return column (serial) must be type integer. -- tests for values using custom queries -- query with one column - failed SELECT * FROM connectby('connectby_int', '1; --', 'parent_keyid', '2', 0) AS t(keyid int, parent_keyid int, level int); ERROR: invalid connectby source data query DETAIL: The query must return at least two columns. -- query with two columns first value as NULL SELECT * FROM connectby('connectby_int', 'NULL::int, 1::int; --', 'parent_keyid', '2', 0) AS t(keyid int, parent_keyid int, level int); keyid | parent_keyid | level -------+--------------+------- 2 | | 0 | 1 | 1 (2 rows) -- query with two columns second value as NULL SELECT * FROM connectby('connectby_int', '1::int, NULL::int; --', 'parent_keyid', '2', 0) AS t(keyid int, parent_keyid int, level int); ERROR: infinite recursion detected -- query with two columns, both values as NULL SELECT * FROM connectby('connectby_int', 'NULL::int, NULL::int; --', 'parent_keyid', '2', 0) AS t(keyid int, parent_keyid int, level int); keyid | parent_keyid | level -------+--------------+------- 2 | | 0 | | 1 (2 rows) -- test for falsely detected recursion DROP TABLE connectby_int; CREATE TABLE connectby_int(keyid int, parent_keyid int); INSERT INTO connectby_int VALUES(11,NULL); INSERT INTO connectby_int VALUES(10,11); INSERT INTO connectby_int VALUES(111,11); INSERT INTO connectby_int VALUES(1,111); -- this should not fail due to recursion detection SELECT * FROM connectby('connectby_int', 'keyid', 'parent_keyid', '11', 0, '-') AS t(keyid int, parent_keyid int, level int, branch text); keyid | parent_keyid | level | branch -------+--------------+-------+---------- 11 | | 0 | 11 10 | 11 | 1 | 11-10 111 | 11 | 1 | 11-111 1 | 111 | 2 | 11-111-1 (4 rows)