Re: COPY enhancements - Mailing list pgsql-hackers

Hi Robert,<br /><br /><blockquote cite="mid:603c8f070909101953y44c262ffn4ea744d235054ab3@mail.gmail.com"
type="cite"><prewrap="">I like this idea, perhaps not surprisingly (for those not following at
 
home: that was my patch).  Unfortunately, it looks to me like there is
no way to do this without overhauling the syntax.  If the existing
syntax required a comma between options (i.e. "copy blah to stdout
binary, oids" rather than "copy to stdout binary oids", this would be
pretty straightforward; but it doesn't even allow one). </pre></blockquote> Well some options like CSV FORCE ... take a
commaseparated list of columns. This would require all options to become reserved keywords or force parenthesis around
optionparameters.<br /><blockquote cite="mid:603c8f070909101953y44c262ffn4ea744d235054ab3@mail.gmail.com"
type="cite"><prewrap="">I wonder if we should consider allowing COPY options to be
 
comma-separated beginning with 8.5, and then require it in 8.6.  Other
options include continuing to support the old syntax for the existing
options, but allowing some new syntax as well and requiring its use
for all new options (this is what we did with EXPLAIN, but there were
only two pre-existing options there), and just changing the syntax
incompatibly and telling users to suck it up.  But I'm not sure I like
either of those choices. </pre></blockquote> We could keep the current syntax for backward compatibility only (can be
droppedin a future release) and have a new syntax (starting in 8.5). To avoid confusion between both, we could just
replaceWITH with something else (or just drop it) to indicate that this is the new syntax.<br /><br /> The new syntax
couldlook like:<br /><pre class="SYNOPSIS">COPY <tt class="REPLACEABLE"><i>tablename</i></tt> [ ( <tt
class="REPLACEABLE"><i>column</i></tt>[, ...] ) ]   FROM { '<tt class="REPLACEABLE"><i>filename</i></tt>' | STDIN }   [
[,BINARY ]     [, OIDS ]     [, DELIMITER [ AS ] '<tt class="REPLACEABLE"><i>delimiter</i></tt>' ]     [, NULL [ AS ]
'<ttclass="REPLACEABLE"><i>null string</i></tt>' ]     [, CSV [ HEADER ]            [ QUOTE [ AS ] '<tt
class="REPLACEABLE"><i>quote</i></tt>']             [ ESCAPE [ AS ] '<tt class="REPLACEABLE"><i>escape</i></tt>' ]
     [ FORCE NOT NULL (<tt class="REPLACEABLE"><i>column</i></tt> [, ...]) ]     [, ERRORS { SKIP |
LOGINTO { tablename | 'filename' }                   [ LABEL label_name ]                   [ KEY key_name ]
      [ MAX ERRORS <i>count</i> ] } ]
 
</pre><br /> Is this what you had in mind?<br /><br /> Emmanuel<br /><pre class="moz-signature" cols="72">-- 
Emmanuel Cecchet
Aster Data Systems
Web: <a class="moz-txt-link-freetext" href="http://www.asterdata.com">http://www.asterdata.com</a>
</pre>