Example to retrieve file from Oracle database:

Here’s an example of how to retrieve a file from an Oracle database using the Oracle PL/SQL language:

  l_blob BLOB;
  -- Select the BLOB from the table
  SELECT file_data INTO l_blob FROM file_table WHERE file_id = 123;

  -- Open a file handle for writing
  l_file := UTL_FILE.FOPEN('/path/to/output/dir', 'file_name.ext', 'wb', 32767);

  -- Write the BLOB to the file
  UTL_FILE.PUT_RAW(l_file, l_blob);

  -- Close the file handle

In this example, we first select the BLOB data from the file_table where the file_id is 123. We then open a file handle using the UTL_FILE package, specifying the output directory, file name, and mode (‘wb’ for write binary). We then use the PUT_RAW procedure to write the BLOB data to the file, and close the file handle using FCLOSE.

Note that you may need to modify this example to suit your specific use case, such as specifying the correct table and column names, and adjusting the file path and name to match your desired output location.

Syntax of getClob method:

The getClob() method is typically used in Java to retrieve data from a database column of the CLOB (Character Large Object) data type. Here is an example of the syntax:

public Clob getClob(int columnIndex) throws SQLException

This method is typically called on a ResultSet object, which is returned from a database query. The columnIndex parameter specifies the index of the column containing the CLOB data in the result set.

Here’s an example usage:

// Assume "conn" is a valid Connection object
PreparedStatement pstmt = conn.prepareStatement("SELECT clob_column FROM my_table WHERE id = ?");
pstmt.setInt(1, 123);

ResultSet rs = pstmt.executeQuery();
if (rs.next()) {
    Clob clob = rs.getClob(1);
    // Do something with the CLOB data, such as reading its contents into a String
    String clobContents = clob.getSubString(1, (int) clob.length());

In this example, we first prepare a SQL statement to select a CLOB column from a table based on an ID parameter. We then execute the query and retrieve the first row of results using rs.next(). We call getClob(1) on the result set to retrieve the CLOB data from the first column, and then use getSubString() to read its contents into a Java String. Note that we cast the clob.length() to an int because getSubString() requires an int parameter for the length.