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Re: Mono and sqlite (again)

tedius — Mon Dec 12, 2005 1:05 pm

Author: tedius

Posted: Mon Dec 12, 2005 1:05 pm

Nordle,

Thanks for that, I do seem to have made a typo there (I have edited it to correct it now) The code wasn't I direct copy as I have cut some stuff out to make it smaller, though essentially it is the same.

As for your comment

Quote:

It says "NOT NULL"

This is for the name and not that value which is what I'm trying to set to null.

If people haven't guessed this is just a simple table that holds key:value pairs. As it happened I would never insert NULL values into this table, but I have other larger ones where inserting NULL values makes more sense than inserting an empty string (my current work around)

RE: Mono and sqlite (again)

nordle — Sun Dec 11, 2005 2:41 pm

Author: nordle

Posted: Sun Dec 11, 2005 2:41 pm

I can't program, so sorry if I've missed the obvious, but the database design sais that it won't allow null values into name. It sais "NOT NULL".

Also, your sql sais insert into _params, not insert into _internal.

Im not sure i've understood / read that right though

Mono and sqlite (again)

tedius — Wed Dec 07, 2005 4:23 pm

Author: tedius

Posted: Wed Dec 07, 2005 4:23 pm

I'm having some more problems with mono and sqlite (version 3).

This time it is that I have a method to insert some values into the data base, and I want to be able to insert NULL values. But I can't find the way to do it.

This is my insert method

Code:

public void Insert(string sName, object oVal)
{
string sql = @"
INSERT INTO _params
(
name,
val
) VALUES
(
:name,
:val
)";

SqliteCommand cmd = new SqliteCommand(sql, mConn);
SqliteParameter param = new SqliteParameter();
param.ParameterName = ":name";
param.Value = sName;
cmd.Parameters.Add(param);

param = new SqliteParameter();
param.ParameterName = ":val";
param.Value = oVal;
cmd.Parameters.Add(param);

cmd.ExecuteNonQuery();
}

The table was created with

Code:

CREATE TABLE _params
(
name TEXT NOT NULL UNIQUE,
val TEXT
)

When I run this code I get a NullRefrenceException, if I try and insert a null. I have also tried to changing the line 'param.Value = oVal;' to

Code:

if (oVal == null)
param.Value = "NULL"; // also tried "\0" and ""
else
param.Value = oVal;

But the code either crashes or uses the value as a string and not a null value.

Can anyone help me insert NULL values via the Parameter object.