Add to TODO:

        o Allow ALTER TABLE to modify column lengths and change to binary
          compatible types


Tom Lane wrote:
> "Christopher Kings-Lynne" <[EMAIL PROTECTED]> writes:
> >> There might be other cases of legal direct change of system catalog 
> >> entries, e,g. varchar to text, if they all are only names for internally 
> >> identical data structures. Can you tell which datatypes may be legally 
> >> interchanged?
> > Yes, you can check if they're binary compatible from the pg_cast table....
> But nearly all of the interesting cases require you to understand the
> type's interpretation of typmod, and you can't learn that from a table.
> How many cases are there where blindly looking for a binary-compatible
> cast in pg_cast will really do you much good?  AFAICS you'd have to set
> atttypmod to -1 if you change atttypid without knowing very specifically
> what you are changing from and to.
>                       regards, tom lane
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