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ORA-22835: Buffer too small for CLOB to CHAR or BLOB to RAW conversion (actual: string, maximum: string)
Cause: An attempt was made to convert CLOB to CHAR or BLOB to RAW, where the LOB size was bigger than the buffer limit for CHAR and RAW types. Note that widths are reported in characters if character length semantics are in effect for the column, otherwise widths are reported in bytes.
Action: Do one of the following:
1. Make the LOB smaller before performing the conversion, for example, by using SUBSTR on CLOB
2. Use DBMS_LOB.SUBSTR to convert CLOB to CHAR or BLOB to RAW.