[Solved] which is the most easiest way to update BLOB value from developer tool?

Using SQLDeveloper

• Open the table which is having a BLOB field, i.e. USERS
• double-click on the BLOB field
• This will open the following pop-up

• 

• Click download in the Saved Data section to download the BLOB content to a File
  • You can click "Text" checkbox to view the data in the pop-up itself
• Update the downloaded file in the text editor and click "Load" in the Local Data section on the pop-up
  • Load will ask you to select the file
  • Select the updated file
  • Commit

Another easy way to do it is to use the oracle replace function on the blob field.

E.g. if you want to change "ValueA" to "ValueB" in the blob:

update MY_TABLE set BLOB_FIELD = replace(BLOB_FIELD, 'ValueA', 'ValueB') where [criteria];

Open the database with the BLOB field by double-clicking USERS on the BLOB field.
With this, the ensuing pop-up will appear.

To download the BLOB information to a File, click download in the Saved Data section.
The info in the pop-up itself can be viewed by selecting the "Text" check box.
In the text editor, modify the downloaded file, then select "Load" in the pop-up window's Local Data section.
You'll be prompted to choose the file by load.
Choose the upgraded version.
Commit