db-derby-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Francois Orsini" <francois.ors...@gmail.com>
Subject Re: Retreive colummn name of a table from java
Date Fri, 15 Sep 2006 07:46:19 GMT
On 9/15/06, yves pielusenet <yvespielusenet@free.fr> wrote:
>
> Ok thank you Francois (are you french as me ?) :)


 De rien Yves :)

I understand now. It should be specified into this doc :
> http://wiki.apache.org/db-derby/ListTableColumns
>
> that schemaname='SYS' is for the example but if we want to retreive
> columns of a personal table, we should use schemaname='APP' :)


That is correct - the example query was for the SYS.SYSCONSTRAINTS system
table/catalog. Good suggestion about the doc. Also, 10.2 version of Derby
now has the IJ 'describe' command to display table columns information (
http://db.apache.org/derby/docs/dev/tools/rtoolsijcomrefdescribe.html).

If you want to try out the 10.2 beta version of Derby - You can find it
here:
http://wiki.apache.org/db-derby/TenTwoSnapshot

Le vendredi 15 septembre 2006 à 00:08 -0700, Francois Orsini a écrit :
> > All the Derby database system tables reside in the 'SYS' schema
> > whereas the default "user" schema is named 'APP'. When you log in to
> > derby, the default schema where the objects are created is 'APP'.
> >
> > In your (own) query, you had not restricted the query against any
> > particular schema, hence it picked it up.
> >
> > On 9/15/06, yves pielusenet <yvespielusenet@free.fr> wrote:
> >         Thank you Francois :)
> >         It works with that schema. but what is the difference between
> >         APP and
> >         SYS ?
> >         And the result is the same as my statement. Is my own wrong ?
> >
> >         Le jeudi 14 septembre 2006 à 23:51 -0700, Francois Orsini a
> >         écrit :
> >         > Ok - Yves, can you try against the schema 'APP' (default)
> >         such as:
> >         >
> >         > ij> select columnnumber, columnname, columndatatype
> >         >    from sys.systables t, sys.syscolumns, sys.sysschemas s
> >         >    where tableid=referenceid and t.schemaid=s.schemaid
> >         >      and schemaname='APP' and tablename='DATA'
> >         >    order by columnnumber;
> >         >
> >         > On 9/14/06, yves pielusenet <yvespielusenet@free.fr> wrote:
> >         >         Yes I have tried it but there is any rows back :(
> >         >
> >         >         ij> select columnnumber, columnname, columndatatype
> >         >            from sys.systables t, sys.syscolumns,
> >         sys.sysschemas s
> >         >            where tableid=referenceid and
> >         t.schemaid=s.schemaid
> >         >              and schemaname='SYS' and tablename='DATA'
> >         >            order by columnnumber;
> >         >         COLUMNNUMB&|COLUMNNAME|COLUMNDATATYPE
> >         >
> >
> ------------------------------------------------------------------------------------------------------------------------------------------------------------
> >         >
> >         >         0 lignes sélectionnées
> >         >
> >         >
> >         >         Le jeudi 14 septembre 2006 à 15:37 -0700, Francois
> >         Orsini a
> >         >         écrit :
> >         >         > Have you tried the following below?
> >         >         >
> >         >         > ij> select columnnumber, columnname,
> >         columndatatype
> >         >         >    from sys.systables t, sys.syscolumns,
> >         sys.sysschemas s
> >         >         >    where tableid=referenceid and
> >         t.schemaid=s.schemaid
> >         >         >      and schemaname='SYS' and tablename='DATA'
> >         >         >    order by columnnumber;
> >         >         >
> >         >         > are you getting any rows back?
> >         >         >
> >         >         > On 9/14/06, yves pielusenet
> >         <yvespielusenet@free.fr> wrote:
> >         >         >         after tests I found this statement :
> >         >         >         ij> select columnname, columnnumber from
> >         >         sys.systables,
> >         >         >         sys.syscolumns where referenceid=tableid
> >         and
> >         >         tablename='DATA'
> >         >         >         order by columnnumber;
> >         >         >
> >         >         >         which works well for me :)
> >         >         >
> >         >         >         do you see something wrong ?
> >         >         >
> >         >         >
> >         >         >         Le jeudi 14 septembre 2006 à 15:16 -0700,
> >         Francois
> >         >         Orsini a
> >         >         >         écrit :
> >         >         >         > Yes,
> >         >         >         >
> >         >         >         > It all depends how you created the table
> >         - have
> >         >         you tried
> >         >         >         running the
> >         >         >         > query by specifying you table name in
> >         uppercase
> >         >         such as:
> >         >         >         > j> select columnnumber, columnname,
> >         columndatatype
> >         >         >         >    from sys.systables t, sys.syscolumns,
> >         >         sys.sysschemas s
> >         >         >         >    where tableid=referenceid and
> >         >         t.schemaid=s.schemaid
> >         >         >         >      and schemaname='SYS' and
> >         tablename='DATA'
> >         >         >         >    order by columnnumber;
> >         >         >         >
> >         >         >         > _or_ you can also run "select * from
> >         >         sys.systables" and find
> >         >         >         out if
> >         >         >         > your table appears in the list being
> >         >         retrieved...then check
> >         >         >         the actual
> >         >         >         > table identifier (aka name)...
> >         >         >         >
> >         >         >         > Hope this helps a bit,
> >         >         >         >
> >         >         >         > --francois
> >         >         >         >
> >         >         >         > On 9/14/06, yves pielusenet
> >         >         <yvespielusenet@free.fr> wrote:
> >         >         >         >         Hello,
> >         >         >         >         I read this :
> >         >         >         >
> >         >         http://wiki.apache.org/db-derby/ListTableColumns
> >         >         >         >
> >         >         >         >         but I can't retreive the column
> >         of my
> >         >         table 'data'.
> >         >         >         Here is
> >         >         >         >         what i
> >         >         >         >         tested :
> >         >         >         >         ij> select columnnumber,
> >         columnname,
> >         >         columndatatype
> >         >         >         >             from sys.systables t,
> >         sys.syscolumns,
> >         >         >         sys.sysschemas s
> >         >         >         >             where tableid=referenceid
> >         and
> >         >         >         t.schemaid=s.schemaid
> >         >         >         >               and schemaname='SYS' and
> >         >         tablename='data'
> >         >         >         >             order by columnnumber;
> >         >         >         >
> >         >         >         >         And the result is :
> >         >         >         >
> >         >         >         >         COLUMNNUMB&|COLUMNNAME|
> >         COLUMNDATATYPE
> >         >         >         >
> >         >         >
> >         >
> >
> ------------------------------------------------------------------------------------------------------------------------------------------------------------
> >         >         >         >
> >         >         >         >         0 lignes sélectionnées
> >         >         >         >
> >         >         >         >         How can I do ?
> >         >         >         >
> >         >         >         >         thanks,
> >         >         >         >
> >         >         >         >         --
> >         >         >         >         yves piel
> >         >         >         >
> >         >         >         >
> >         >         >         >
> >         >         >
> >         >         >
> >         >
> >         >
> >
> >
>
>

Mime
View raw message