Although CLOBs are not supported by PRPC, notes and the associated articles from the PRPC Help System:

SQL connectors cannot process columns of data type ARRAY, IMAGE, or CLOB (Character Large Object). 

https://pdn.pega.com/sites/pdn.pega.com/files/help_v62/procomhelpmain.htm#rule-/rule-connect-/rule-connect-sql/related.htm

https://pdn.pega.com/sites/pdn.pega.com/files/help_v62/procomhelpmain.htm#rule-/rule-connect-/rule-connect-sql/sqlguidelineshtm.htm

I was able to search the Support Portal and found this and thought it might prove helpful:

The following is a workaround that uses the java code (invoked from an activity) to retrieve the clob data and gets past the 4K limitation. The database ( Data-Admin-DB-Name ) is configured to connect using a JDBC url.

try
{
HashStringMap keysMap = new HashStringMap();
keysMap.put("pyRWDatabase","PMLandingTable");
keysMap.put("pxObjClass","Data-Admin-DB-Name");
ClipboardPage dbPage = tools.getDatabase().open(keysMap,false);

java.sql.Connection Conn = java.sql.DriverManager.getConnection(dbPage.getString("pyDatabaseURL"),dbPage.getString("pyDBUser"),dbPage.getString("pyDBPassword"));
java.sql.PreparedStatement cs= Conn.prepareStatement("select RECORD_UID, CUST_INC_STMNT from SERVICE_RECORD_LANDING_FINAL where RECORD_UID = 1038");
java.sql.ResultSet result = cs.executeQuery();

if (result.next()) {
String id = result.getString(1); // the uid
java.sql.Clob clb = result.getClob(2); // the blob
int clobLength = (int) clb.length();

StringBuilder sb = new StringBuilder();
java.io.Reader reader = clb.getCharacterStream();
java.io.BufferedReader br = new java.io.BufferedReader(reader);

String clobData;

while(null != (clobData = br.readLine())) {
sb.append(clobData);
}

String prntString = sb.toString();

br.close();
clb.free();

}
else
{
oLog.error("No Id found ");
}
//Cleanup DB resourses
result.close();
cs.close();
Conn.close();
} catch (Exception e){
oLog.error("Exception encountered" + e);
e.printStackTrace();
}

Hope this helps,

Sean

Pega Academy