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From Suresh Thalamati <suresh.thalam...@gmail.com>
Subject Re: getColumns(...) and quoted table names ?
Date Thu, 23 Jun 2005 18:11:15 GMT
Thanks Francois,  your explanation  was  realy  helpful.

-suresh

Francois Orsini wrote:

>The quotes are there for the parser to treat the table object
>(ansi-92) identifier as case sensitive and for the reason you
>mentioned when dealing with objects that have reserved words as
>identifiers...
>
>The metadata DatabaseMetaData.getColumns() method does not really take
>a table name per-se (to be picky), but more like a table name
>"pattern" following the JDBC pattern-matching format convention ('%'
>and '_' characters can be used).
>
>I believe the way it is expressed currently in the getColumns() or
>getTables() metadata calls is correct as underneath, system catalogs
>get queried via an (internal) SQL statement which takes a 
>case-sensitive string as search predicate to select the matching
>tuples - in your case matching the table name expressed in uppercase
>will match the table you created (obviously).
>
>One thing you could also do is new'ing a DbTable object for the
>qualifying resultset row that matches the table you are looking for
>with a getTables() call (using a qualifying/restrictive pattern) and
>then specificy the table name to use in the getColumns() call via a
>DbTable.getTableName() call...you might want to do this if you want to
>ensure you are dealing with a valid table satisfying your search
>before returning the columns...
>
>Just some thoughts...
>
>--francois
>
>On 6/22/05, Suresh Thalamati <suresh.thalamati@gmail.com> wrote:
>  
>
>>I have  a table that uses reserved word as name , so it is quoted like :
>>create table "ORDER"(a int ) ;
>>All  SQL queries seems to expect it as quoted name , except Database
>>Metadata getColumns(..).
>>
>> DatabaseMetaData dmd = conn.getMetaData();
>> ResultSet rs = dmd.getColumns(null, null , "\"ORDER\"" , null) ;
>> does not return  any column information , where as
>>
>> ResultSet rs = dmd.getColumns(null, null , "ORDER"" , null) ;
>> retunns the  "ORDER"  table columns Information.
>>
>> I am wondering what  is the correct usage here ,  i.e  does metadata
>>calls suppose to
>> expect   quoted tables names like SQL or  the  one without quotes ?
>>
>>Thanks
>>-suresht
>>
>>
>>
>>
>>    
>>
>
>  
>



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