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\connect dblink_test_slave
create table foo(f1 int, f2 text, f3 text[], primary key (f1,f2));
NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index 'foo_pkey' for table 'foo'
insert into foo values(0,'a','{"a0","b0","c0"}');
insert into foo values(1,'b','{"a1","b1","c1"}');
insert into foo values(2,'c','{"a2","b2","c2"}');
insert into foo values(3,'d','{"a3","b3","c3"}');
insert into foo values(4,'e','{"a4","b4","c4"}');
insert into foo values(5,'f','{"a5","b5","c5"}');
insert into foo values(6,'g','{"a6","b6","c6"}');
insert into foo values(7,'h','{"a7","b7","c7"}');
insert into foo values(8,'i','{"a8","b8","c8"}');
insert into foo values(9,'j','{"a9","b9","c9"}');
\connect dblink_test_master
-- regular old dblink
select * from dblink('dbname=dblink_test_slave','select * from foo') as t(a int, b text, c text[]) where t.a > 7;
a | b | c
---+---+------------
8 | i | {a8,b8,c8}
9 | j | {a9,b9,c9}
(2 rows)
-- should generate "no connection available" error
select * from dblink('select * from foo') as t(a int, b text, c text[]) where t.a > 7;
ERROR: dblink: no connection available
-- create a persistent connection
select dblink_connect('dbname=dblink_test_slave');
dblink_connect
----------------
OK
(1 row)
-- use the persistent connection
select * from dblink('select * from foo') as t(a int, b text, c text[]) where t.a > 7;
a | b | c
---+---+------------
8 | i | {a8,b8,c8}
9 | j | {a9,b9,c9}
(2 rows)
-- open a cursor
select dblink_open('rmt_foo_cursor','select * from foo');
dblink_open
-------------
OK
(1 row)
-- fetch some data
select * from dblink_fetch('rmt_foo_cursor',4) as t(a int, b text, c text[]);
a | b | c
---+---+------------
0 | a | {a0,b0,c0}
1 | b | {a1,b1,c1}
2 | c | {a2,b2,c2}
3 | d | {a3,b3,c3}
(4 rows)
select * from dblink_fetch('rmt_foo_cursor',4) as t(a int, b text, c text[]);
a | b | c
---+---+------------
4 | e | {a4,b4,c4}
5 | f | {a5,b5,c5}
6 | g | {a6,b6,c6}
7 | h | {a7,b7,c7}
(4 rows)
-- this one only finds two rows left
select * from dblink_fetch('rmt_foo_cursor',4) as t(a int, b text, c text[]);
a | b | c
---+---+------------
8 | i | {a8,b8,c8}
9 | j | {a9,b9,c9}
(2 rows)
-- close the cursor
select dblink_close('rmt_foo_cursor');
dblink_close
--------------
OK
(1 row)
-- should generate "cursor rmt_foo_cursor does not exist" error
select * from dblink_fetch('rmt_foo_cursor',4) as t(a int, b text, c text[]);
ERROR: dblink_fetch: cursor rmt_foo_cursor does not exist
-- close the persistent connection
select dblink_disconnect();
dblink_disconnect
-------------------
OK
(1 row)
-- should generate "no connection available" error
select * from dblink('select * from foo') as t(a int, b text, c text[]) where t.a > 7;
ERROR: dblink: no connection available
-- put more data into our slave table, first using arbitrary connection syntax
-- but truncate the actual return value so we can use diff to check for success
select substr(dblink_exec('dbname=dblink_test_slave','insert into foo values(10,''k'',''{"a10","b10","c10"}'')'),1,6);
substr
--------
INSERT
(1 row)
-- create a persistent connection
select dblink_connect('dbname=dblink_test_slave');
dblink_connect
----------------
OK
(1 row)
-- put more data into our slave table, using persistent connection syntax
-- but truncate the actual return value so we can use diff to check for success
select substr(dblink_exec('insert into foo values(11,''l'',''{"a11","b11","c11"}'')'),1,6);
substr
--------
INSERT
(1 row)
-- let's see it
select * from dblink('select * from foo') as t(a int, b text, c text[]);
a | b | c
----+---+---------------
0 | a | {a0,b0,c0}
1 | b | {a1,b1,c1}
2 | c | {a2,b2,c2}
3 | d | {a3,b3,c3}
4 | e | {a4,b4,c4}
5 | f | {a5,b5,c5}
6 | g | {a6,b6,c6}
7 | h | {a7,b7,c7}
8 | i | {a8,b8,c8}
9 | j | {a9,b9,c9}
10 | k | {a10,b10,c10}
11 | l | {a11,b11,c11}
(12 rows)
-- change some data
select dblink_exec('update foo set f3[2] = ''b99'' where f1 = 11');
dblink_exec
-------------
UPDATE 1
(1 row)
-- let's see it
select * from dblink('select * from foo') as t(a int, b text, c text[]) where a = 11;
a | b | c
----+---+---------------
11 | l | {a11,b99,c11}
(1 row)
-- delete some data
select dblink_exec('delete from foo where f1 = 11');
dblink_exec
-------------
DELETE 1
(1 row)
-- let's see it
select * from dblink('select * from foo') as t(a int, b text, c text[]) where a = 11;
a | b | c
---+---+---
(0 rows)
-- misc utilities
\connect dblink_test_slave
-- show the currently executing query
select 'hello' as hello, dblink_current_query() as query;
hello | query
-------+-----------------------------------------------------------
hello | select 'hello' as hello, dblink_current_query() as query;
(1 row)
-- list the primary key fields
select * from dblink_get_pkey('foo');
position | colname
----------+---------
1 | f1
2 | f2
(2 rows)
-- build an insert statement based on a local tuple,
-- replacing the primary key values with new ones
select dblink_build_sql_insert('foo','1 2',2,'{"0", "a"}','{"99", "xyz"}');
dblink_build_sql_insert
-----------------------------------------------------------
INSERT INTO foo(f1,f2,f3) VALUES('99','xyz','{a0,b0,c0}')
(1 row)
-- build an update statement based on a local tuple,
-- replacing the primary key values with new ones
select dblink_build_sql_update('foo','1 2',2,'{"0", "a"}','{"99", "xyz"}');
dblink_build_sql_update
----------------------------------------------------------------------------------------
UPDATE foo SET f1 = '99', f2 = 'xyz', f3 = '{a0,b0,c0}' WHERE f1 = '99' AND f2 = 'xyz'
(1 row)
-- build a delete statement based on a local tuple,
select dblink_build_sql_delete('foo','1 2',2,'{"0", "a"}');
dblink_build_sql_delete
---------------------------------------------
DELETE FROM foo WHERE f1 = '0' AND f2 = 'a'
(1 row)
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