There is an error in your example for the prepare statement on page
http://developer.postgresql.org/docs/postgres/sql-prepare.html.
Using the example from the link above
rainstorm=> PREPARE fooplan (int, text, bool, numeric(8,2)) AS
rainstorm-> INSERT INTO foo VALUES($1, '$2', '$3', '$4');
ERROR: invalid input syntax for type boolean: "$3"
Taking out the single quotes around the boolean parameter 3 yields
rainstorm=> PREPARE fooplan (int, text, bool, numeric(8,2)) AS
rainstorm-> INSERT INTO foo VALUES($1, '$2', $3, '$4');
ERROR: invalid input syntax for type real: "$4"
So take out the single quotes around the numeric parameter 4 yields
rainstorm=> PREPARE fooplan (int, text, bool, numeric(8,2)) AS
rainstorm-> INSERT INTO foo VALUES($1, '$2', $3, $4);
PREPARE
rainstorm=> EXECUTE fooplan(1, 'Hunter Valley', 't', '200.00');
INSERT 0 1
So that "works", but what it does is
rainstorm=> select * from foo;
key | address | valid | cost
-----+---------+-------+------
1 | $2 | t | 200
(1 row)
It inserts the literal string of parameter two rather than the value provided for parameter 2. This is in the
PostgreSQL8 beta 4 Windows native version.
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