DROP TABLE IF EXISTS sequence; 
CREATE TABLE sequence ( 
     name VARCHAR(50) NOT NULL, 
     current_value INT NOT NULL, 
     increment INT NOT NULL DEFAULT 1, 
     PRIMARY KEY (name) 
) ENGINE=InnoDB; 

DROP FUNCTION IF EXISTS currval; 
DELIMITER $ 
CREATE FUNCTION currval (seq_name VARCHAR(50)) 
     RETURNS INTEGER 
     LANGUAGE SQL 
     DETERMINISTIC 
     CONTAINS SQL 
     SQL SECURITY DEFINER 
     COMMENT '' 
BEGIN 
     DECLARE value INTEGER; 
     SET value = 0; 
     SELECT current_value INTO value 
          FROM sequence 
          WHERE name = seq_name; 
     RETURN value; 
END 
$ 
DELIMITER ; 

DROP FUNCTION IF EXISTS nextval; 
DELIMITER $ 
CREATE FUNCTION nextval (seq_name VARCHAR(50)) 
     RETURNS INTEGER 
     LANGUAGE SQL 
     DETERMINISTIC 
     CONTAINS SQL 
     SQL SECURITY DEFINER 
     COMMENT '' 
BEGIN 
     UPDATE sequence 
          SET current_value = current_value + increment 
          WHERE name = seq_name; 
     RETURN currval(seq_name); 
END 
$ 
DELIMITER ; 

DROP FUNCTION IF EXISTS setval; 
DELIMITER $ 
CREATE FUNCTION setval (seq_name VARCHAR(50), value INTEGER) 
     RETURNS INTEGER 
     LANGUAGE SQL 
     DETERMINISTIC 
     CONTAINS SQL 
     SQL SECURITY DEFINER 
     COMMENT '' 
BEGIN 
     UPDATE sequence 
          SET current_value = value 
          WHERE name = seq_name; 
     RETURN currval(seq_name); 
END 
$ 
DELIMITER ; 

public void testGetSequence() { 
  Connection conn = JDBCUtils.getConnection(url, userName, password); 
  String sql = "SELECT CURRVAL('TestSeq');"; 
  PreparedStatement ptmt = null; 
  ResultSet rs = null; 
  try { 
    ptmt = conn.prepareStatement(sql); 
    rs = ptmt.executeQuery(); 
    int count = 0; 
    while (rs.next()) { 
      count = rs.getInt(1); 
    } 
    System.out.println(count); 
  } catch (SQLException e) { 
    e.printStackTrace(); 
  } finally { 
    JDBCUtils.close(rs, ptmt, conn); 
  } 
} 

DROP TABLE IF EXISTS sequence; 
 
-- 建sequence表，指定seq列为无符号大整型，可支持无符号值：0(default)到18446744073709551615（0到2^64–1）。
CREATE TABLE sequence (
   name       VARCHAR(50) NOT NULL, 
     current_value   BIGINT UNSIGNED NOT NULL DEFAULT 0, 
     increment     INT NOT NULL DEFAULT 1, 
     PRIMARY KEY (name)  -- 不允许重复seq的存在。
) ENGINE=InnoDB; 
 
 
DELIMITER / 
 
DROP FUNCTION IF EXISTS currval /
 
CREATE FUNCTION currval(seq_name VARCHAR(50)) 
RETURNS BIGINT
BEGIN
     DECLARE value BIGINT;
     SELECT current_value INTO value
     FROM sequence
     WHERE upper(name) = upper(seq_name); -- 大小写不区分.
     RETURN value;
END;
/
 
DELIMITER ; 
 
 
DELIMITER /
 
DROP FUNCTION IF EXISTS nextval /
 
CREATE FUNCTION nextval (seq_name VARCHAR(50)) 
RETURNS BIGINT 
BEGIN 
     DECLARE value BIGINT;
     UPDATE sequence 
     SET current_value = current_value + increment 
     WHERE upper(name) = upper(seq_name);
     RETURN currval(seq_name); 
END;
/
 
DELIMITER ; 
 
DELIMITER /
 
DROP FUNCTION IF EXISTS setval / 
 
CREATE FUNCTION setval (seq_name VARCHAR(50), value BIGINT) 
RETURNS BIGINT
BEGIN 
     UPDATE sequence 
     SET current_value = value 
     WHERE upper(name) = upper(seq_name); 
     RETURN currval(seq_name); 
END;
/
 
DELIMITER ;

mysql> insert into sequence set name='myseq';

mysql> select * from sequence;

+-------+---------------+-----------+
| name | current_value | increment |
+-------+---------------+-----------+
| myseq |       0 |     1 |
+-------+---------------+-----------+
1 row in set (0.00 sec)

mysql> select nextval('myseq');

+------------------+
| nextval('myseq') |
+------------------+
|        1 |
+------------------+
1 row in set (0.00 sec)