Re: pgsql: Add psql tab completion for DO blocks.

itagaki@postgresql.org (Takahiro Itagaki) writes:
> Add psql tab completion for DO blocks.
> Also adjust documentation of DO.

This syntax synopsis is completely nuts:

DO { [ LANGUAGE <replaceable class="PARAMETER">lang_name</replaceable> ] | <replaceable
class="PARAMETER">code</replaceable>} ... 

It implies that an empty string is a valid substitute for the { ... }
construct, since I could take the first choice and then omit the
optional bracketed construct.

I think that it would be logically correct without the square brackets,
but as a matter of clarity I really doubt it's an improvement over the
original.

            regards, tom lane