diff options
Diffstat (limited to 'contrib/dblink/doc/query')
| -rw-r--r-- | contrib/dblink/doc/query | 45 |
1 files changed, 37 insertions, 8 deletions
diff --git a/contrib/dblink/doc/query b/contrib/dblink/doc/query index 525ffab45a2..9c814177417 100644 --- a/contrib/dblink/doc/query +++ b/contrib/dblink/doc/query @@ -6,17 +6,19 @@ dblink -- Returns a set from a remote database Synopsis dblink(text connstr, text sql) -- or - +dblink(text connname, text sql) dblink(text sql) Inputs + connname connstr + If two arguments are present, the first is first assumed to be a specific + connection name to use. If the name is not found, the argument is then + assumed to be a valid connection string, of standard libpq format, + e.g.: "hostaddr=127.0.0.1 dbname=mydb user=postgres password=mypasswd" - standard libpq format connection string, - e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd" - If the second form is used, then the dblink_connect(text connstr) must be - executed first. + If only one argument is used, then the unnamed connection is used. sql @@ -29,7 +31,7 @@ Outputs Example usage -test=# select * from dblink('dbname=template1','select proname, prosrc from pg_proc') +select * from dblink('dbname=template1','select proname, prosrc from pg_proc') as t1(proname name, prosrc text) where proname like 'bytea%'; proname | prosrc ------------+------------ @@ -47,13 +49,13 @@ test=# select * from dblink('dbname=template1','select proname, prosrc from pg_p byteaout | byteaout (12 rows) -test=# select dblink_connect('dbname=template1'); +select dblink_connect('dbname=template1'); dblink_connect ---------------- OK (1 row) -test=# select * from dblink('select proname, prosrc from pg_proc') +select * from dblink('select proname, prosrc from pg_proc') as t1(proname name, prosrc text) where proname like 'bytea%'; proname | prosrc ------------+------------ @@ -71,6 +73,33 @@ test=# select * from dblink('select proname, prosrc from pg_proc') byteaout | byteaout (12 rows) +select dblink_connect('myconn','dbname=regression'); + dblink_connect +---------------- + OK +(1 row) + +select * from dblink('myconn','select proname, prosrc from pg_proc') + as t1(proname name, prosrc text) where proname like 'bytea%'; + proname | prosrc +------------+------------ + bytearecv | bytearecv + byteasend | byteasend + byteale | byteale + byteagt | byteagt + byteage | byteage + byteane | byteane + byteacmp | byteacmp + bytealike | bytealike + byteanlike | byteanlike + byteacat | byteacat + byteaeq | byteaeq + bytealt | bytealt + byteain | byteain + byteaout | byteaout +(14 rows) + + ================================================================== A more convenient way to use dblink may be to create a view: |