createLob method

Create a temporary Large Object (LOB) for storing large data.

Creates a temporary LOB in the database that can be used to store and manipulate large text or binary data. Similar to python-oracledb's createlob().

Parameters:

• lobType: Type of LOB to create:
  • LobType.clob - Character LOB (for text data)
  • LobType.blob - Binary LOB (for binary data)
  • LobType.nclob - National Character LOB (for Unicode text)

Returns: An OracleLob object for reading/writing large data.

Example - Creating and Writing CLOB:

final clob = await connection.createLob(LobType.clob);
try {
  await clob.write('This is a large text document...');

  // Insert the LOB into a table
  await connection.execute(
    'INSERT INTO documents (id, content) VALUES (:1, :2)',
    params: [docId, clob],
  );
  await connection.commit();
} finally {
  clob.dispose();
}

Example - Creating and Writing BLOB:

final blob = await connection.createLob(LobType.blob);
try {
  // Write binary data (e.g., image file)
  final imageBytes = await File('photo.jpg').readAsBytes();
  await blob.write(imageBytes);

  await connection.execute(
    'UPDATE employees SET photo = :1 WHERE id = :2',
    params: [blob, employeeId],
  );
  await connection.commit();
} finally {
  blob.dispose();
}

Important:

• Always call dispose() on LOBs when done to free resources
• Temporary LOBs exist only for the session duration
• Call commit to persist LOB data in the database

See also:

• OracleLob for LOB operations
• OracleLob.read to read LOB data
• OracleLob.write to write LOB data