SQL Workbench/J fully suppports BLOB (and CLOB) columns. BLOB data can be displayed and updated from within the result of a SELECT query.
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SQL Workbench/J also supports direct uploading of BLOB files from the client to the server:

INSERT INTO person (id,firstname,lastname,photo) VALUES (1,'Arthur','Dent',{$blobfile=c:/temp/hitchguide.bmp});

The extended syntax is also supported for UPDATE statements and is independent of the DBMS. It is only limited by the level of JDBC compliance of the driver.

WbExport and WbImport fully support BLOB columns when exporting to text ("flat files") or XML files.

For more details, please read the manual.