java,mysql-为什么不从一个表中获取最后一个插入的id,然后再将其插入到另一个表中?
这是一个重复的问题。我又放了一次,因为它给了我错误 我正在创建一个组,它将插入m_组 我需要获取组ID和组创建者ID并将其插入 M_GROUP_MEMBERS表为GROUP_ID INT,MEMBER_ID INT 我的代码是java,mysql-为什么不从一个表中获取最后一个插入的id,然后再将其插入到另一个表中?,java,mysql,Java,Mysql,这是一个重复的问题。我又放了一次,因为它给了我错误 我正在创建一个组,它将插入m_组 我需要获取组ID和组创建者ID并将其插入 M_GROUP_MEMBERS表为GROUP_ID INT,MEMBER_ID INT 我的代码是 public void groupCreation(String groupname, int grouptype, int creator_id) { DatabaseService oDatabaseService = new DatabaseService
public void groupCreation(String groupname, int grouptype, int creator_id) {
DatabaseService oDatabaseService = new DatabaseService();
Connection connection = oDatabaseService.connect();
try {
Statement stmt,stmt2 = null;
stmt = connection.createStatement();
stmt2 = connection.createStatement();
String sql;
String sql2;
sql = "INSERT INTO M_GROUPS(GROUP_NAME,GROUP_CREATOR_ID,GROUP_TYPE,CREATION_TIME)"
+ " VALUES ('"
+ groupname
+ "','"
+ creator_id
+ "','"
+ grouptype + "',NOW())";
//stmt.executeUpdate(sql);
stmt.executeUpdate(sql,Statement.RETURN_GENERATED_KEYS);
ResultSet rs = stmt.getGeneratedKeys();
rs.next();
int key = rs.getInt(1);
System.out.println(key);
sql2 = "INSERT INTO M_GROUP_MEMBERS(GROUP_ID,MEMBER_ID,JOIN_TIME)"
+ " VALUES ('"
+ key
+ "','"
+ creator_id
+ "',NOW())";
stmt2.executeUpdate(sql2);
} catch (SQLException se) {
se.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (connection != null)
connection.close();
} catch (SQLException se) {
se.printStackTrace();
}
}
}
它给我的输出像
18
java.sql.SQLException: Column count doesn't match value count at row 1
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1078)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4190)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4122)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2570)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2731)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2812)
at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1811)
at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1725)
at org.uims.service.GroupService.groupCreation(GroupService.java:106)
at org.uims.servlet.GroupServlet.doPost(GroupServlet.java:66)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:646)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:315)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
我用这种方法解决这个问题
public void groupCreation(String groupname, int grouptype, int creator_id) {
DatabaseService oDatabaseService = new DatabaseService();
Connection connection = oDatabaseService.connect();
Statement stmt = null;
Statement stmt2 = null;
Statement stmt3 = null;
try {
//Statement stmt = null;
stmt = connection.createStatement();
String sql;
sql = "INSERT INTO M_GROUPS(GROUP_NAME,GROUP_CREATOR_ID,GROUP_TYPE,CREATION_TIME)"
+ " VALUES ('"
+ groupname
+ "','"
+ creator_id
+ "','"
+ grouptype + "',NOW())";
stmt.executeUpdate(sql);
stmt.close();
stmt2 = connection.createStatement();
String sql2;
sql2 ="select max(group_id)as group_id from m_groups where group_creator_id='"+ creator_id+ "'";
//System.out.println("before rs for sql2");
ResultSet rs = stmt2.executeQuery(sql2);
//System.out.println("after rs for sql2");
int groupId = 0 ;
while (rs.next()) {
groupId =rs.getInt("group_id");
}
System.out.println(groupId);
stmt3 = connection.createStatement();
String sql3;
sql3 = "INSERT INTO M_GROUP_MEMBERS(GROUP_ID,MEMBER_ID,JOIN_TIME)"
+ " VALUES ('"
+ groupId
+ "','"
+ creator_id
+ "',NOW())";
stmt3.executeUpdate(sql3);
} catch (SQLException se) {
se.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
try{
if(stmt!=null)
stmt.close();
}catch(SQLException se2){
}// nothing can do
try{
if(stmt2!=null)
stmt2.close();
}catch(SQLException se3){
}// nothing can do
try{
if(stmt3!=null)
stmt3.close();
}catch(SQLException se4){
}// nothing can do
try {
if (connection != null)
connection.close();
} catch (SQLException se) {
se.printStackTrace();
}
}
}
我不明白为什么第二个语句会导致像上面那样的异常。您确定导致错误的不是对
groupCreation
的后续调用中第一条语句的错误吗?在执行SQL查询之前,请尝试打印它们。顺便说一下,您可能希望考虑使用PeriaReSQL语句,而不是将SQL字符串串联起来;如果组名是”,0,0,NOW());删除表M_组--代码>?在变量替换后打印SQL语句。您可能会发现其中一个变量值中有一个单引号。第一个SQL语句似乎很完美。因为sysout成功地打印了值18
。下一行似乎有错误。@wahid_cse:代码的哪一部分是第106行?是stmt2.executeUpdate(sql2)代码>@Ravinder是它是stmt2.executeUpdate(sql2);