The UNION operator, as we have seen, does not like the CLOB datatype. My solution was to convert the CLOB datatype to VARCHAR2 which has a 4,000-character limit. So you will not be able to UNION two views and obtain more than 4,000 characters from the CLOB column.
One thing you can do is to pull the CLOB values from the views in a subsequent operation. But this will have to be performed without the UNION operator.
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