dblink_connect — opens a persistent connection to a remote database
dblink_connect(text connstr) returns text dblink_connect(text connname, text connstr) returns text
dblink_connect() establishes a connection to a remote PostgreSQL database. The server and database to be contacted are identified through a standard libpq connection string. Optionally, a name can be assigned to the connection. Multiple named connections can be open at once, but only one unnamed connection is permitted at a time. The connection will persist until closed or until the database session is ended.
The connection string may also be the name of an existing foreign server. It is recommended to use the foreign-data wrapper
dblink_fdw when defining the foreign server. See the example below, as well as CREATE SERVER and CREATE USER MAPPING.
The name to use for this connection; if omitted, an unnamed connection is opened, replacing any existing unnamed connection.
libpq-style connection info string, for example
hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd options=-csearch_path=. For details see Section 34.1.1. Alternatively, the name of a foreign server.
# Return Value
Returns status, which is always
OK (since any error causes the function to throw an error instead of returning).
If untrusted users have access to a database that has not adopted a secure schema usage pattern, begin each session by removing publicly-writable schemas from
search_path. One could, for example, add
connstr. This consideration is not specific to
dblink; it applies to every interface for executing arbitrary SQL commands.
Only superusers may use
dblink_connect to create non-password-authenticated connections. If non-superusers need this capability, use
It is unwise to choose connection names that contain equal signs, as this opens a risk of confusion with connection info strings in other
SELECT dblink_connect('dbname=postgres options=-csearch_path='); dblink_connect