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From "Jean T. Anderson" <...@bristowhill.com>
Subject Re: derby user
Date Fri, 16 Dec 2005 18:44:50 GMT
meenakshi selvi wrote:
> hi
> 1.is there any way to describe the table in ij tools.

You can execute SQL select statements that query the system tables. The 
system tables are listed here


Obtaining the description for a table is pretty simple if you just want 
the column names and types; for example, given this table:

    ij> create table hotelavailability
    (hotel_id int not null,
    booking_date date not null,
    rooms_taken int default 0,
    primary key (hotel_id, booking_date)

This query gets you the information in the sys.systables table:

   select * from sys.systables where tablename = 'HOTELAVAILABILITY';

This query gets the columns for that table:

    ij> select c.columnnumber,
    from   sys.syscolumns c, sys.systables t
    where  c.referenceid=t.tableid
    and    t.tablename='HOTELAVAILABILITY'
    order by 1;

    1          |HOTEL_ID               |INTEGER NOT NULL
    2          |BOOKING_DATE           |DATE NOT NULL
    3          |ROOMS_TAKEN            |INTEGER

    3 rows selected

Add a join to sys.syscontraints to get constraint information -- here's 
where the query can start getting really messy.  dblook might be an 
easier option; see the next point.

> 2.is there any way to show the tables in a database.

dblook dumps the schema for a database or table; for more information, see




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