RE: Does Null == ""?

[Jon Frisby]

> I didn't know that.  What *does* it do if you specify a 
> string literal that's smaller than the CHAR(20) field, then?  
> Pad it with binary zeros?

MySQL returns a properly trimmed string, although it will allocate a
fixed amount of space for the storage.  Other databases pad with blank
spaces.


> > One solution I've seen proposed is to allow the programmer to define
> > NULL as an enumeration.  Basically "this value can contain 
> a *value*, or
> > it can contain one of N specific NULL values that I define".
> 
> I assume that this would be done by the database designer 
> rather than the programmer!  It sounds reasonable enough, but 
> possibly overengineering.

A slip of the tongue (fingers) on my part...  The DB designer would be
allowed to define the possible meanings of NULL for a column as part of
the schema.

-JF