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From Andreas Wagner <andreas.josef.wag...@googlemail.com>
Subject Re: Deleting column names
Date Wed, 23 Apr 2014 14:47:15 GMT
Thanks :) This works ...

Kind regards
Andreas


On 04/22/2014 06:05 PM, Laing, Michael wrote:
> Your understanding is incorrect - the easiest way to see that is to 
> try it.
>
>
> On Tue, Apr 22, 2014 at 12:00 PM, Sebastian Schmidt <isibboi@gmail.com 
> <mailto:isibboi@gmail.com>> wrote:
>
>     From my understanding, this would delete all entries with the
>     given s. Meaning, if I have inserted (sa, p1, o1, c1) and (sa, p2,
>     o2, c2), executing this:
>
>     DELETE FROM table_name WHERE s = sa AND p = p1 AND o = o1 AND c = c1
>
>     would delete sa, p1, o1, c1, p2, o2, c2. Is this correct? Or does
>     the above statement only delete p1, o1, c1?
>
>
>     2014-04-22 4:00 GMT+02:00 Steven A Robenalt <srobenal@stanford.edu
>     <mailto:srobenal@stanford.edu>>:
>
>         Is there a reason you can't use:
>
>         DELETE FROM table_name WHERE s = ? AND p = ? AND o = ? AND c = ?;
>
>
>         On Mon, Apr 21, 2014 at 6:51 PM, Eric Plowe
>         <eric.plowe@gmail.com <mailto:eric.plowe@gmail.com>> wrote:
>
>             Also I don't think you can null out columns that are part
>             of the primary key after they've been set.
>
>
>             On Monday, April 21, 2014, Andreas Wagner
>             <andreas.josef.wagner@googlemail.com
>             <mailto:andreas.josef.wagner@googlemail.com>> wrote:
>
>                 Hi cassandra users, hi Sebastian,
>
>                 I'd be interested in this ... is there any
>                 update/solution?
>
>                 Thanks so much ;)
>                 Andreas
>
>                 On 04/16/2014 11:43 AM, Sebastian Schmidt wrote:
>
>                     Hi,
>
>                     I'm using a Cassandra table to store some data. I
>                     created the table like
>                     this:
>                     CREATE TABLE IF NOT EXISTS table_name (s BLOB, p
>                     BLOB, o BLOB, c BLOB,
>                     PRIMARY KEY (s, p, o, c));
>
>                     I need the at least the p column to be sorted, so
>                     that I can use it in a
>                     WHERE clause. So as far as I understand, the s
>                     column is now the row
>                     key, and (p, o, c) is the column name.
>
>                     I tried to delete single entries with a prepared
>                     statement like this:
>                     DELETE p, o, c FROM table_name WHERE s = ? AND p =
>                     ? AND o = ? AND c = ?;
>
>                     That didn't work, because p is a primary key part.
>                     It failed during
>                     preparation.
>
>                     I also tried to use variables like this:
>                     DELETE ?, ?, ? FROM table_name WHERE s = ?;
>
>                     This also failed during preparation, because ? is
>                     an unknown identifier.
>
>
>                     Since I have multiple different p, o, c
>                     combinations per s, deleting the
>                     whole row identified by s is no option. So how can
>                     I delete a s, p, o, c
>                     tuple, without deleting other s, p, o, c tuples
>                     with the same s? I know
>                     that this worked with Thrift/Hector before.
>
>                     Regards,
>                     Sebastian
>
>
>
>
>
>         -- 
>         Steve Robenalt
>         Software Architect
>         HighWire | Stanford University
>         425 Broadway St, Redwood City, CA 94063
>
>         srobenal@stanford.edu <mailto:srobenal@stanford.edu>
>         http://highwire.stanford.edu
>
>         /
>         /
>
>
>
>
>


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