Re: JDBC and CLOB retrieval question

From:
Lew <lew@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Wed, 26 Sep 2007 19:11:04 -0400
Message-ID:
<6_udnWiw8bWVemfbnZ2dnUVZ_sqinZ2d@comcast.com>
Martin Gregorie wrote:

I'm using JDBC to access a PostgresQL [sic] database which contains TEXT
fields. That's the Postgres equivalent of a CLOB. I'm storing strings in
this field with PreparedStatement.setCharacterStream() and getting them
back with ResultSet.getCharacterStream() - this works well, but the code
I use to read the data back is ugly:

   private String retrieveText(ResultSet rs, String column)
         throws SQLException
   {
      StringBuffer buff = new StringBuffer();
      try
      {
         Reader tr = rs.getCharacterStream(column);
         char[] cbuf = new char[50];
         int n;

         while ((n = tr.read(cbuf, 0, 50)) != -1)
            buff.append(cbuf);

         tr.close();
      }
      catch (IOException e)
      {
         ....
      }
      return buff.toString();
   }

It works, but is there something a bit more elegant that I should be
using instead of reading chunks via the the loop?

I've probably missed something that should be obvious, so any hints
would be welcome.


Try ResultSet.getString( String column ).
<http://java.sun.com/javase/6/docs/api/java/sql/ResultSet.html#getString(java.lang.String)>
and the setString() equivalent.

TEXT is also Postgres's version of LONG VARCHAR and works like an
unlimited-length VARCHAR.

--
Lew

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