sqlite_mismatch using etc.c.sqlite3

[Jacho Mendt]

Hello everyone, I'm currently working on a prototype database 
system, but I'm kinda new to D and to sqlite3. The fragment of 
code that gives me problems looks like this:

extern(C) int myCallback(void *a_parm, int argc, char **argv,
char **column)
{
      return 0;
}



int new_entity(sqlite3* db)
{
	const(char)* sql="SELECT ID FROM ENTITY;";
	int result;
	result=sqlite3_exec(db,sql,&myCallback,null,null);
         writeln(result);
	if (SQLITE_OK!=result)
	{ return -1;}
         return 0;
}

sqlite3_exec here returns 21, wich is the code for 
SQLITE_MISMATCH. I know I'm doing something wrong, i just can't 
find what.