Re: Using DEFAULT as a parameter value with PQexecPrepare()

I simplified my example somewhat. I usually have six of these "optional" parameters.
The number of prepared statements would be too many for this approach.

I will follow your advice in the cases where I just one or two of the "optional" parameters.

Looks like I will need to dynamically build my SQL command as:

INSERT INTO t ( c1, c2, c5, c8, c11 ) VALUES ( $1, $2, $3, $4, $5 );

when the number of "optional" parameters is larger.

I can at least use PQexecParams() to get some SQL injection protection and avoid the escaping and quoting of the parameter values.

Thanks for the advice

-----Original Message-----
From: pgsql-general-owner(at)postgresql(dot)org [mailto:pgsql-general-owner(at)postgresql(dot)org] On Behalf Of Greg Sabino Mullane
Sent: Thursday, April 05, 2012 7:18 PM
To: pgsql-general(at)postgresql(dot)org
Subject: Re: [GENERAL] Using DEFAULT as a parameter value with PQexecPrepare()

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> I was looking for a to use a prepared statement for this operation.
>
> PREPARE myinsert AS "INSERT INTO t ( c1, c2, c3, c4, c5) VALUES ( $1, $2, $3, $4, $5);
>
> Now I want to execute this prepared statement something like:
>
> EXECUTE myinsert ( 'abc', 1, DEFAULT, 9, 3);
>
> Is there any way to specify the column's default value as a parameter value?

You will need to have separate prepared statements. In the case above,
you can use either:

PREPARE myinsert2 AS INSERT INTO t(c1,c2,c3,c4,c5) VALUES ($1,$2,DEFAULT,$3,$4);

or

PREPARE myinsert2 AS INSERT INTO t(c1,c2,c4,c5) VALUES ($1,$2,$3,$4);

- --
Greg Sabino Mullane greg(at)turnstep(dot)com
End Point Corporation http://www.endpoint.com/
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