formating and spelling fixes to my last doc update
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@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/Attic/jdbc.sgml,v 1.31 2001/11/26 19:07:11 momjian Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/Attic/jdbc.sgml,v 1.32 2001/11/27 01:20:17 barry Exp $
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-->
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<chapter id="jdbc">
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@ -379,9 +379,8 @@ db.close();
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Any time you want to issue <acronym>SQL</acronym> statements to
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the database, you require a <classname>Statement</classname> or
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<classname>PreparedStatement</classname> instance. Once you have
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a <classname>Statement</classname> or <classname>PreparedStatement
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</classname>, you
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can use issue a
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a <classname>Statement</classname> or
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<classname>PreparedStatement</classname>, you can use issue a
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query. This will return a <classname>ResultSet</classname>
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instance, which contains the entire result. <xref
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linkend="jdbc-query-example"> illustrates this process.
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@ -406,7 +405,7 @@ st.close();
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</para>
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<para>
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This example will issues the same query as before using
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This example will issue the same query as before using
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a <classname>PreparedStatement</classname>
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and a bind value in the query.
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<programlisting>
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@ -430,7 +429,8 @@ st.close();
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<para>
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The following must be considered when using the
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<classname>Statement</classname> interface:
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<classname>Statement</classname> or
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<classname>PreparedStatement</classname> interface:
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<itemizedlist>
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<listitem>
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@ -440,7 +440,8 @@ st.close();
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open the connection and use it for the connection's
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lifetime. But you have to remember that only one
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<classname>ResultSet</classname> can exist per
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<classname>Statement</classname> at a given time.
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<classname>Statement</classname> or
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<classname>PreparedStatement</classname> at a given time.
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</para>
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</listitem>
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@ -464,7 +465,8 @@ st.close();
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<listitem>
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<para>
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When you are done using the <classname>Statement</classname>
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you should close the <classname>Statement</classname>.
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or <classname>PreparedStatement</classname>
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you should close it.
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</para>
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</listitem>
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</itemizedlist>
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@ -532,6 +534,8 @@ st.close();
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update, or delete statement.
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</para>
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<example id="jdbc-delete-example">
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<title>Simple Delete Example</title>
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<para>
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This example will issue a simple delete and print out the number
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of rows deleted.
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@ -544,6 +548,7 @@ System.out.println(rowsDeleted + " rows deleted");
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st.close();
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</programlisting>
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</para>
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</example>
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</sect1>
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<sect1 id="jdbc-ddl">
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@ -557,6 +562,8 @@ st.close();
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however it doesn't return a result.
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</para>
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<example id="jdbc-drop-table-example">
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<title>Drop Table Example</title>
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<para>
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This example will drop a table.
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<programlisting>
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@ -565,18 +572,20 @@ ResultSet rs = st.executeQuery("DROP TABLE mytable");
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st.close();
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</programlisting>
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</para>
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</example>
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</sect1>
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<sect1 id="jdbc-binary-data">
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<title>Storing Binary Data</title>
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<para>
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<application>PostgreSQL</application> provides two distinct way to
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<application>PostgreSQL</application> provides two distinct ways to
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store binary data. Binary data can be stored in a table using
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<application>PostgreSQL's</application> binary datatype
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<type>bytea</type>, or by using the <firstterm>Large Object</firstterm>
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feature which stores the binary data in a separate table in a special
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format, and refers to from your own tables by an <type>OID</type> value.
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format, and refers to that table by storing a value of type
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<type>OID</type> in your table.
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</para>
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<para>
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@ -598,8 +607,8 @@ st.close();
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</para>
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<para>
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7.2 is the first release that the <acronym>JDBC</acronym> Driver
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supports the <type>bytea</type> datatype. The introduction of
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7.2 is the first release of the <acronym>JDBC</acronym> Driver
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that supports the <type>bytea</type> datatype. The introduction of
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this functionality in 7.2 has introduced a change in behavior
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as compared to previous releases. In 7.2 the methods
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<function>getBytes()</function>, <function>setBytes()</function>,
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@ -702,7 +711,7 @@ ps.close();
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</para>
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<para>
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Here you can see how the Large Object is retrieved as an
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Here the binary data was retrieved as an
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<classname>byte[]</classname>. You could have used a
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<classname>InputStream</classname> object instead.
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</para>
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@ -721,6 +730,8 @@ CREATE TABLE imagesLO (imgname text, imgOID OID);
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<programlisting>
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// All LargeObject API calls must be within a transaction
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conn.setAutoCommit(false);
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// Get the Large Object Manager to perform operations with
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LargeObjectManager lobj = ((org.postgresql.Connection)conn).getLargeObjectAPI();
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//create a new large object
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@ -760,6 +771,8 @@ fis.close();
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<programlisting>
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// All LargeObject API calls must be within a transaction
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conn.setAutoCommit(false);
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// Get the Large Object Manager to perform operations with
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LargeObjectManager lobj = ((org.postgresql.Connection)conn).getLargeObjectAPI();
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PreparedStatement ps = con.prepareStatement("SELECT imgOID FROM imagesLO WHERE imgname=?");
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@ -775,7 +788,7 @@ if (rs != null) {
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byte buf[] = new byte[obj.size()];
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obj.read(buf, 0, obj.size());
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//do something with the data read here
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}
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// Close the object
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obj.close();
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}
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