CLOB binding in WHERE clause

I have the following situation:
A table "ExampleTable" with a column of type CLOB. I want to search the table by this CLOB field. If I had a VARCHAR2 field I would write:
SELECT ... FROM ExampleTable WHERE MY_VARCHAR2_Field='my_search_criteria';

This does not not work with CLOB. I found that I can write:

SELECT ... FROM ExampleTable WHERE MY_CLOB_Field LIKE 'my_search_criteria';

That does work for CLOB length of 3 kByte but for 4 kByte large CLOB fields (and larger) it does not work any longer.

I use the DBI interface of perl which uses the OCI libraries from Oracle.

How can I overcome this limit or is it not possible ?

Thomas

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