我看到别人写的东西里面String StrSql = update " + tablename+ " set " +
" USER_ID = @@userID , " +
" where ID = @@id";
有@@我没有搞懂为什么用@@不用可以么?望高手指点
" USER_ID = @@userID , " +
" where ID = @@id";
有@@我没有搞懂为什么用@@不用可以么?望高手指点
如果id为字符串update tableName set id = '2'
{ private final static String tableName = "USER_NEGATIVE";
private final static String sequenceName = tableName + "_SEQ";
private long userID;
private long negativeID;
public UserNegative()
{
}
public UserNegative(long id)
{
setId(id);
}
public olean validate()
{
return true;
}
public long getUserID()
{
return userID;
}
public void setUserID(long aUserID)
{
userID = aUserID;
}
public long getNegativeID()
{
return negativeID;
}
public void setNegativeID(long aNegativeID)
{
negativeID = aNegativeID;
} public void insert(Connection conn) throws SQLException
{
Manager.log.debug(this, "insert --> Begin ");
Hashtable values = new Hashtable();
String StrSql = "insert into " + tableName + " (" +
"ID ," +
"USER_ID ," +
"NEGATIVE_ID " +
") values( " +
"@@id , " +
"@@userID , " +
"@@negativeID " +
")";
retrieveSeqNum(conn , sequenceName);
values.put("id", new Long(getId()));
values.put("userID", new Long(userID));
values.put("negativeID", new Long(negativeID));
super.insert(conn, StrSql, values);
Manager.log.debug(this, "insert --> End ");
}
public void update(Connection conn) throws SQLException
{
Manager.log.debug(this, "update --> Begin ");
Hashtable values = new Hashtable();
String StrSql = "update " + tableName + " set " +
" USER_ID = @@userID , " +
" NEGATIVE_ID = @@negativeID " +
" where ID = @@id";
values.put("id" , new Long(getId()));
values.put("userID", new Long(userID));
values.put("negativeID", new Long(negativeID));
super.update(conn, StrSql, values);
Manager.log.debug(this, "update --> End ");
}
public void delete(Connection conn) throws SQLException
{
Manager.log.debug(this, "delete --> Begin ");
Hashtable values = new Hashtable();
String StrSql = "delete from " + tableName + " where ID = @@id";
values.put("id" , new Long(getId()));
super.delete(conn, StrSql, values);
Manager.log.debug(this, "delete --> End ");
}
public void retrieve(Connection conn) throws SQLException
{
Manager.log.debug(this, "retrieve --> Begin ");
Hashtable values = new Hashtable();
String StrSql = "select " +
"USER_ID ," +
"NEGATIVE_ID " +
" from " + tableName + " where ID = @@id";
values.put("id" , new Long(getId()));
DataSet rs = super.retrieve(conn, StrSql, values);
if (rs.getRowSize() == 1)
{
setUserID(Long.parseLong(rs.getString(0,1 - 1 )));
setNegativeID(Long.parseLong(rs.getString(0,2 - 1 )));
}
Manager.log.debug(this, "retrieve --> End ");
}
}