JDBC Type 4 Driver 2.0 Programmer's Reference (SQL/MX 2.x)

Reading Unicode data from a CLOB Column

To read Unicode or MBCS data from a CLOB column, use the CLOB interface or Reader.

Using the CLOB interface:

// Obtain the Clob from ResultSet

Clob myClob = rs.getClob("myClobColumn");

// Obtain the input stream to read Clob data

Reader cs = myClob.getCharacterStream();

// read Clob data using Reader

char[] myClobData;

myClobData = new char[length];

cs.read(myClobData, offset, length);

To read Unicode data from a CLOB column by using a Reader:

// obtain the Reader from ResultSet

Reader cs = rs.getCharacterStream("myClobColumn");

// read Clob data using the InputStream

char[] myClobData;

myClobData = new char[length];

css.read(myClobData, offset, length);

Updating CLOB Data

Updating Clob Objects with the updateClob Method

Replacing Clob Objects

To update CLOB data, use the methods in the Clob interface or use the updateClob method of the

ResultSet interface. The Type 4 driver makes changes directly to the CLOB data. Therefore, the Type

4 driver returns false to the locatorsUpdateCopy method of the DatabaseMetaData

interface. Applications do not need to issue a separate update statement to update the CLOB data.

Make updates to CLOB data in the following ways:

Updating Clob Objects with the updateClob Method●

Replacing Clob Objects●

Updating Clob Objects with the updateClob Method

Unlike some LOB support implementations, the Type 4 driver updates the CLOB data directly in the

database. So, when the Clob object is same in the updateClob method as the Clob object obtained

using getClob, the updateRow method of the ResultSet interface does nothing with the Clob

object.