If you need the value before insert a row:
CREATE FUNCTION `getAutoincrementalNextVal`(`TableName` VARCHAR(50))
RETURNS BIGINT
LANGUAGE SQL
NOT DETERMINISTIC
CONTAINS SQL
SQL SECURITY DEFINER
COMMENT ''
BEGIN
DECLARE Value BIGINT;
SELECT
AUTO_INCREMENT INTO Value
FROM
information_schema.tables
WHERE
table_name = TableName AND
table_schema = DATABASE();
RETURN Value;
END
You can use this in a insert:
INSERT INTO
document (Code, Title, Body)
VALUES (
sha1( concat (convert ( now() , char), ' ', getAutoincrementalNextval ('document') ) ),
'Title',
'Body'
);