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convert String a Blob

Jhonnathan Emilio Cardona Saineda
Ranch Hand

Joined: Jan 24, 2012
Posts: 38

hello, thanks in advance.
In the Oracle database, I have a blob type data.
How I can store a String with PreparedStatement using the method setBlob()?
i used this but don't work

byte byte_string[]=string.getBytes();
Blob blob= new SerialBlob(byte_string);
preparedStatement.setBlob(1, blob);

java.lang.ClassCastException: javax.sql.rowset.serial.SerialBlob cannot be cast to oracle.sql.BLOB

Thank you.

Sorry for my English, I'll improve
Martin Vajsar

Joined: Aug 22, 2010
Posts: 3733

Well, the first problem is that String contains character data, while BLOB contains binary data. Are you sure you shouldn't be using a CLOB, which is designed to hold characters? You're currently going around this issue by converting the String to bytes, but it entails character set conversion to your default locale and it might not be what you need.

Oracle won't accept a Blob or Clob created using the new operator. This thread contains a code that can be used to store a BLOB or CLOB in Oracle, and references to two other threads.
I agree. Here's the link:
subject: convert String a Blob
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