Clob data not fetching by select adapter service

in a table ,data type of a column is CLOB.when I am trying to fetch the clob data by selecting adapter service randomly for few records its not able to fetch.but when tracing its coming properly but when I am trying to run the service few records are randomly not coming.

Below is the column expression

expression columntype jdbc type o/p field type o/p field
X CLOB CLOB java.lang.String Y

Try to reload the adapter values on the adapter service.

Apart from trying the above option also what is the connection type you are using transactional or no transaction or XA?..Is it a MS SQL or Oracle DB?