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|
-- Adjust this setting to control where the objects get created.
SET search_path = public;
--
-- Define the functions and test data
-- therein.
--
-- Turn off echoing so that expected file does not depend on
-- contents of dblink.sql.
\set ECHO none
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"}');
-- misc utilities
-- 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)
-- too many pk fields, should fail
SELECT dblink_build_sql_insert('foo','1 2 3 4',4,'{"0", "a", "{a0,b0,c0}"}','{"99", "xyz", "{za0,zb0,zc0}"}');
ERROR: number of primary key fields exceeds number of specified relation attributes
-- 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)
-- too many pk fields, should fail
SELECT dblink_build_sql_update('foo','1 2 3 4',4,'{"0", "a", "{a0,b0,c0}"}','{"99", "xyz", "{za0,zb0,zc0}"}');
ERROR: number of primary key fields exceeds number of specified relation attributes
-- 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)
-- too many pk fields, should fail
SELECT dblink_build_sql_delete('foo','1 2 3 4',4,'{"0", "a", "{a0,b0,c0}"}');
ERROR: number of primary key fields exceeds number of specified relation attributes
-- retest using a quoted and schema qualified table
CREATE SCHEMA "MySchema";
CREATE TABLE "MySchema"."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 "MySchema"."Foo" VALUES (0,'a','{"a0","b0","c0"}');
-- list the primary key fields
SELECT *
FROM dblink_get_pkey('"MySchema"."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('"MySchema"."Foo"','1 2',2,'{"0", "a"}','{"99", "xyz"}');
dblink_build_sql_insert
------------------------------------------------------------------------
INSERT INTO "MySchema"."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('"MySchema"."Foo"','1 2',2,'{"0", "a"}','{"99", "xyz"}');
dblink_build_sql_update
-----------------------------------------------------------------------------------------------------
UPDATE "MySchema"."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('"MySchema"."Foo"','1 2',2,'{"0", "a"}');
dblink_build_sql_delete
----------------------------------------------------------
DELETE FROM "MySchema"."Foo" WHERE f1 = '0' AND f2 = 'a'
(1 row)
-- regular old dblink
SELECT *
FROM dblink('dbname=regression','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=regression');
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=regression','SET autocommit TO ''on'';INSERT INTO foo VALUES(10,''k'',''{"a10","b10","c10"}'')'),1,6);
substr
--------
INSERT
(1 row)
-- create a persistent connection
SELECT dblink_connect('dbname=regression');
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('SET autocommit TO ''on'';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('SET autocommit TO ''on'';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('SET autocommit TO ''on'';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)
-- close the persistent connection
SELECT dblink_disconnect();
dblink_disconnect
-------------------
OK
(1 row)
|
