Re: [HACKERS] Enhancing PGSQL to be compatible with Informix SQL

On Fri, 7 Jan 2000, Thomas Lockhart wrote:

> > the best would be to implement ANSI outer joins, and then use the
> > rewriter to allow for the Oracle syntax, or something similar, just to
> > add readability to the SQL.
>
> When I tried adding the syntax to gram.y a while ago it gave
> shift/reduce errors on the "(+)" fields. I would guess that we would
> need to have this become a token in the lexer :((
>

I'd actually expect a potential reduce/reduce conflict between:

a_expr:
func_name '(' ... ')'
and a_expr '(' '+' ')'

since func_name is a ColID as is a_expr potentially, so the system must
work out whether the ColID reduces to an a_expr when it sees then '('
which it can't do (it needs another token to work that out).

So yes, you probably need a new lexer token.

> I'll have the code in gram.y (commented out) when I commit my next
> changes for this; someone can play with it if they want.
>
> - Thomas
>
> --
> Thomas Lockhart lockhart(at)alumni(dot)caltech(dot)edu
> South Pasadena, California
>

.............................Rod

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