86 lines
2.0 KiB
Plaintext
86 lines
2.0 KiB
Plaintext
==================================================================
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Name
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dblink -- Returns a set from a remote database
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Synopsis
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dblink(text connstr, text sql)
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- or -
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dblink(text sql)
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Inputs
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connstr
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standard libpq format connection string,
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e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"
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If the second form is used, then the dblink_connect(text connstr) must be
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executed first.
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sql
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sql statement that you wish to execute on the remote host
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e.g. "select * from pg_class"
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Outputs
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Returns setof record
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Example usage
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test=# select * from dblink('dbname=template1','select proname, prosrc from pg_proc')
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as t1(proname name, prosrc text) where proname like 'bytea%';
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proname | prosrc
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------------+------------
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byteacat | byteacat
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byteaeq | byteaeq
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bytealt | bytealt
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byteale | byteale
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byteagt | byteagt
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byteage | byteage
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byteane | byteane
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byteacmp | byteacmp
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bytealike | bytealike
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byteanlike | byteanlike
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byteain | byteain
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byteaout | byteaout
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(12 rows)
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test=# select dblink_connect('dbname=template1');
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dblink_connect
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----------------
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OK
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(1 row)
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test=# select * from dblink('select proname, prosrc from pg_proc')
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as t1(proname name, prosrc text) where proname like 'bytea%';
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proname | prosrc
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------------+------------
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byteacat | byteacat
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byteaeq | byteaeq
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bytealt | bytealt
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byteale | byteale
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byteagt | byteagt
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byteage | byteage
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byteane | byteane
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byteacmp | byteacmp
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bytealike | bytealike
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byteanlike | byteanlike
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byteain | byteain
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byteaout | byteaout
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(12 rows)
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==================================================================
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A more convenient way to use dblink may be to create a view:
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create view myremote_pg_proc as
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select *
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from dblink('dbname=template1','select proname, prosrc from pg_proc')
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as t1(proname name, prosrc text);
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Then you can simply write:
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select * from myremote_pg_proc where proname like 'bytea%';
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