CLOB CLOB data type

A CLOB (character large object) value can be up to 2,147,483,647 characters long. A CLOB is used to store unicode character-based data, such as large documents in any character set.

The length is given in number characters for both CLOB, unless one of the suffixes K, M, or G is given, relating to the multiples of 1024, 1024*1024, 1024*1024*1024 respectively.

Length is specified in characters (unicode) for CLOB.
Syntax {CLOB |CHARACTER LARGE OBJECT}(length [{{K |M |G}]))

Corresponding Compile-Time Java Type

java.sql.Clob

JDBC Metadata Type (java.sql.Types)

CLOB
Corresponding Compile-Time Java Type

java.sql.Clob

JDBC Metadata Type (java.sql.Types)

CLOB

Use the getClob method on the java.sql.ResultSet to retrieve a CLOB handle to the underlying data.

Related Information

See .

import java.sql.*; public class clob { public static void main(String[] args) { try { String url = "jdbc:derby:clobberyclob;create=true"; Class.forName("org.apache.derby.jdbc.EmbeddedDriver").newInstance(); Connection conn = DriverManager.getConnection(url); Statement s = conn.createStatement(); s.executeUpdate("CREATE TABLE documents (id INT, text CLOB(64 K))"); conn.commit(); // --- add a file java.io.File file = new java.io.File("asciifile.txt"); int fileLength = (int) file.length(); // - first, create an input stream java.io.InputStream fin = new java.io.FileInputStream(file); PreparedStatement ps = conn.prepareStatement("INSERT INTO documents VALUES (?, ?)"); ps.setInt(1, 1477); // - set the value of the input parameter to the input stream ps.setAsciiStream(2, fin, fileLength); ps.execute(); conn.commit(); // --- reading the columns ResultSet rs = s.executeQuery("SELECT text FROM documents WHERE id = 1477"); while (rs.next()) { java.sql.Clob aclob = rs.getClob(1); java.io.InputStream ip = rs.getAsciiStream(1); int c = ip.read(); while (c > 0) { System.out.print((char)c); c = ip.read(); } System.out.print("\n"); // ... } } catch (Exception e) { System.out.println("Error! "+e); } } }