JDBC Type 4 Driver 1.1 Programmer's Reference

Updating BLOB Data
Updating Blob Objects by Using the updateBlob Method
Replacing Blob Objects
To update BLOB data, use the methods in the Blob interface or use the updateBlob method
of the ResultSet interface. The Type 4 driver makes changes to the BLOB data directly.
Therefore, the Type 4 driver returns false to the locatorsUpdateCopy method of the
DatabaseMetaData interface. Applications do not need to issue a separate update statement
to update the BLOB data.
Update BLOB data in the following ways.
Updating Blob Objects by using the updateBlob Method●
Replacing Blob Objects●
Updating Blob Objects by Using the updateBlob Method
Unlike some LOB support implementations, the Type 4 driver updates the BLOB data directly
in the database. So, when the Blob object is same in the updateBlob method as the object
obtained using getBlob, the updateRow method of the ResultSet interface does nothing
with the Blob object.
When the Blob objects differ, the Blob object in the updateBlob method behaves as if the
setBlob method was issued. See Inserting a Blob Object with the setBlob Method.
Replacing Blob Objects
You can replace Blob objects in the following ways:
Use the EMPTY_BLOB() function to replace the Blob object with the empty Blob
object.
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Replace an existing Blob object in a row by inserting the Blob with new data as
described under Inserting a BLOB Column Using the Blob Interface.
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Use the setBinaryStream() method to of the PreparedStatement interface to
replace the existing Blob object with new BLOB data.
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Use the setBlob or updateBlob methods to replace the existing BLOB objects as
explained under Inserting a Blob Object with the setBlob Method and Updating Blob
Objects with the UpdateBlob Method.
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