I want to INSERT a record in a database (which is Microsoft SQL Server in my case) using JDBC in Java. At the same time, I want to obtain the insert ID. How can I achieve this using JDBC API?
If it is an auto generated key, then you can use Statement#getGeneratedKeys() for this. You need to call it on the same Statement as the one being used for the INSERT. You first need to create the statement using Statement.RETURN_GENERATED_KEYS to notify the JDBC driver to return the keys.
Here's a basic example:
public void create(User user) throws SQLException {
try (
Connection connection = dataSource.getConnection();
PreparedStatement statement = connection.prepareStatement(SQL_INSERT,
Statement.RETURN_GENERATED_KEYS);
) {
statement.setString(1, user.getName());
statement.setString(2, user.getPassword());
statement.setString(3, user.getEmail());
// ...
int affectedRows = statement.executeUpdate();
if (affectedRows == 0) {
throw new SQLException("Creating user failed, no rows affected.");
}
try (ResultSet generatedKeys = statement.getGeneratedKeys()) {
if (generatedKeys.next()) {
user.setId(generatedKeys.getLong(1));
}
else {
throw new SQLException("Creating user failed, no ID obtained.");
}
}
}
}
Note that you're dependent on the JDBC driver as to whether it works. Currently, most of the last versions will work, but if I am correct, Oracle JDBC driver is still somewhat troublesome with this. MySQL and DB2 already supported it for ages. PostgreSQL started to support it not long ago. I can't comment about MSSQL as I've never used it.
For Oracle, you can invoke a CallableStatement with a RETURNING clause or a SELECT CURRVAL(sequencename) (or whatever DB-specific syntax to do so) directly after the INSERT in the same transaction to obtain the last generated key. See also this answer.
Create Generated Column
String generatedColumns[] = { "ID" };
Pass this geneated Column to your statement
PreparedStatement stmtInsert = conn.prepareStatement(insertSQL, generatedColumns);
Use ResultSet object to fetch the GeneratedKeys on Statement
ResultSet rs = stmtInsert.getGeneratedKeys();
if (rs.next()) {
long id = rs.getLong(1);
System.out.println("Inserted ID -" + id); // display inserted record
}
When encountering an 'Unsupported feature' error while using Statement.RETURN_GENERATED_KEYS, try this:
String[] returnId = { "BATCHID" };
String sql = "INSERT INTO BATCH (BATCHNAME) VALUES ('aaaaaaa')";
PreparedStatement statement = connection.prepareStatement(sql, returnId);
int affectedRows = statement.executeUpdate();
if (affectedRows == 0) {
throw new SQLException("Creating user failed, no rows affected.");
}
try (ResultSet rs = statement.getGeneratedKeys()) {
if (rs.next()) {
System.out.println(rs.getInt(1));
}
rs.close();
}
Where BATCHID is the auto generated id.
I'm hitting Microsoft SQL Server 2008 R2 from a single-threaded JDBC-based application and pulling back the last ID without using the RETURN_GENERATED_KEYS property or any PreparedStatement. Looks something like this:
private int insertQueryReturnInt(String SQLQy) {
ResultSet generatedKeys = null;
int generatedKey = -1;
try {
Statement statement = conn.createStatement();
statement.execute(SQLQy);
} catch (Exception e) {
errorDescription = "Failed to insert SQL query: " + SQLQy + "( " + e.toString() + ")";
return -1;
}
try {
generatedKey = Integer.parseInt(readOneValue("SELECT ##IDENTITY"));
} catch (Exception e) {
errorDescription = "Failed to get ID of just-inserted SQL query: " + SQLQy + "( " + e.toString() + ")";
return -1;
}
return generatedKey;
}
This blog post nicely isolates three main SQL Server "last ID" options:
http://msjawahar.wordpress.com/2008/01/25/how-to-find-the-last-identity-value-inserted-in-the-sql-server/ - haven't needed the other two yet.
Instead of a comment, I just want to answer post.
Interface java.sql.PreparedStatement
columnIndexes « You can use prepareStatement function that accepts columnIndexes and SQL statement.
Where columnIndexes allowed constant flags are Statement.RETURN_GENERATED_KEYS1 or Statement.NO_GENERATED_KEYS[2], SQL statement that may contain one or more '?' IN parameter placeholders.
SYNTAX «
Connection.prepareStatement(String sql, int autoGeneratedKeys)
Connection.prepareStatement(String sql, int[] columnIndexes)
Example:
PreparedStatement pstmt =
conn.prepareStatement( insertSQL, Statement.RETURN_GENERATED_KEYS );
columnNames « List out the columnNames like 'id', 'uniqueID', .... in the target table that contain the auto-generated keys that should be returned. The driver will ignore them if the SQL statement is not an INSERT statement.
SYNTAX «
Connection.prepareStatement(String sql, String[] columnNames)
Example:
String columnNames[] = new String[] { "id" };
PreparedStatement pstmt = conn.prepareStatement( insertSQL, columnNames );
Full Example:
public static void insertAutoIncrement_SQL(String UserName, String Language, String Message) {
String DB_URL = "jdbc:mysql://localhost:3306/test", DB_User = "root", DB_Password = "";
String insertSQL = "INSERT INTO `unicodeinfo`( `UserName`, `Language`, `Message`) VALUES (?,?,?)";
//"INSERT INTO `unicodeinfo`(`id`, `UserName`, `Language`, `Message`) VALUES (?,?,?,?)";
int primkey = 0 ;
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection conn = DriverManager.getConnection(DB_URL, DB_User, DB_Password);
String columnNames[] = new String[] { "id" };
PreparedStatement pstmt = conn.prepareStatement( insertSQL, columnNames );
pstmt.setString(1, UserName );
pstmt.setString(2, Language );
pstmt.setString(3, Message );
if (pstmt.executeUpdate() > 0) {
// Retrieves any auto-generated keys created as a result of executing this Statement object
java.sql.ResultSet generatedKeys = pstmt.getGeneratedKeys();
if ( generatedKeys.next() ) {
primkey = generatedKeys.getInt(1);
}
}
System.out.println("Record updated with id = "+primkey);
} catch (InstantiationException | IllegalAccessException | ClassNotFoundException | SQLException e) {
e.printStackTrace();
}
}
I'm using SQLServer 2008, but I have a development limitation: I cannot use a new driver for it, I have to use "com.microsoft.jdbc.sqlserver.SQLServerDriver" (I cannot use "com.microsoft.sqlserver.jdbc.SQLServerDriver").
That's why the solution conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS) threw a java.lang.AbstractMethodError for me.
In this situation, a possible solution I found is the old one suggested by Microsoft:
How To Retrieve ##IDENTITY Value Using JDBC
import java.sql.*;
import java.io.*;
public class IdentitySample
{
public static void main(String args[])
{
try
{
String URL = "jdbc:microsoft:sqlserver://yourServer:1433;databasename=pubs";
String userName = "yourUser";
String password = "yourPassword";
System.out.println( "Trying to connect to: " + URL);
//Register JDBC Driver
Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver").newInstance();
//Connect to SQL Server
Connection con = null;
con = DriverManager.getConnection(URL,userName,password);
System.out.println("Successfully connected to server");
//Create statement and Execute using either a stored procecure or batch statement
CallableStatement callstmt = null;
callstmt = con.prepareCall("INSERT INTO myIdentTable (col2) VALUES (?);SELECT ##IDENTITY");
callstmt.setString(1, "testInputBatch");
System.out.println("Batch statement successfully executed");
callstmt.execute();
int iUpdCount = callstmt.getUpdateCount();
boolean bMoreResults = true;
ResultSet rs = null;
int myIdentVal = -1; //to store the ##IDENTITY
//While there are still more results or update counts
//available, continue processing resultsets
while (bMoreResults || iUpdCount!=-1)
{
//NOTE: in order for output parameters to be available,
//all resultsets must be processed
rs = callstmt.getResultSet();
//if rs is not null, we know we can get the results from the SELECT ##IDENTITY
if (rs != null)
{
rs.next();
myIdentVal = rs.getInt(1);
}
//Do something with the results here (not shown)
//get the next resultset, if there is one
//this call also implicitly closes the previously obtained ResultSet
bMoreResults = callstmt.getMoreResults();
iUpdCount = callstmt.getUpdateCount();
}
System.out.println( "##IDENTITY is: " + myIdentVal);
//Close statement and connection
callstmt.close();
con.close();
}
catch (Exception ex)
{
ex.printStackTrace();
}
try
{
System.out.println("Press any key to quit...");
System.in.read();
}
catch (Exception e)
{
}
}
}
This solution worked for me!
I hope this helps!
You can use following java code to get new inserted id.
ps = con.prepareStatement(query, Statement.RETURN_GENERATED_KEYS);
ps.setInt(1, quizid);
ps.setInt(2, userid);
ps.executeUpdate();
ResultSet rs = ps.getGeneratedKeys();
if (rs.next()) {
lastInsertId = rs.getInt(1);
}
It is possible to use it with normal Statement's as well (not just PreparedStatement)
Statement statement = conn.createStatement();
int updateCount = statement.executeUpdate("insert into x...)", Statement.RETURN_GENERATED_KEYS);
try (ResultSet generatedKeys = statement.getGeneratedKeys()) {
if (generatedKeys.next()) {
return generatedKeys.getLong(1);
}
else {
throw new SQLException("Creating failed, no ID obtained.");
}
}
Most others have suggested to use JDBC API for this, but personally, I find it quite painful to do with most drivers. When in fact, you can just use a native T-SQL feature, the OUTPUT clause:
try (
Statement s = c.createStatement();
ResultSet rs = s.executeQuery(
"""
INSERT INTO t (a, b)
OUTPUT id
VALUES (1, 2)
"""
);
) {
while (rs.next())
System.out.println("ID = " + rs.getLong(1));
}
This is the simplest solution for SQL Server as well as a few other SQL dialects (e.g. Firebird, MariaDB, PostgreSQL, where you'd use RETURNING instead of OUTPUT).
I've blogged about this topic more in detail here.
With Hibernate's NativeQuery, you need to return a ResultList instead of a SingleResult, because Hibernate modifies a native query
INSERT INTO bla (a,b) VALUES (2,3) RETURNING id
like
INSERT INTO bla (a,b) VALUES (2,3) RETURNING id LIMIT 1
if you try to get a single result, which causes most databases (at least PostgreSQL) to throw a syntax error. Afterwards, you may fetch the resulting id from the list (which usually contains exactly one item).
In my case ->
ConnectionClass objConnectionClass=new ConnectionClass();
con=objConnectionClass.getDataBaseConnection();
pstmtGetAdd=con.prepareStatement(SQL_INSERT_ADDRESS_QUERY,Statement.RETURN_GENERATED_KEYS);
pstmtGetAdd.setString(1, objRegisterVO.getAddress());
pstmtGetAdd.setInt(2, Integer.parseInt(objRegisterVO.getCityId()));
int addId=pstmtGetAdd.executeUpdate();
if(addId>0)
{
ResultSet rsVal=pstmtGetAdd.getGeneratedKeys();
rsVal.next();
addId=rsVal.getInt(1);
}
If you are using Spring JDBC, you can use Spring's GeneratedKeyHolder class to get the inserted ID.
See this answer...
How to get inserted id using Spring Jdbctemplate.update(String sql, obj...args)
If you are using JDBC (tested with MySQL) and you just want the last inserted ID, there is an easy way to get it. The method I'm using is the following:
public static Integer insert(ConnectionImpl connection, String insertQuery){
Integer lastInsertId = -1;
try{
final PreparedStatement ps = connection.prepareStatement(insertQuery);
ps.executeUpdate(insertQuery);
final com.mysql.jdbc.PreparedStatement psFinal = (com.mysql.jdbc.PreparedStatement) ps;
lastInsertId = (int) psFinal.getLastInsertID();
connection.close();
} catch(SQLException ex){
System.err.println("Error: "+ex);
}
return lastInsertId;
}
Also, (and just in case) the method to get the ConnectionImpl is the following:
public static ConnectionImpl getConnectionImpl(){
ConnectionImpl conexion = null;
final String dbName = "database_name";
final String dbPort = "3306";
final String dbIPAddress = "127.0.0.1";
final String connectionPath = "jdbc:mysql://"+dbIPAddress+":"+dbPort+"/"+dbName+"?autoReconnect=true&useSSL=false";
final String dbUser = "database_user";
final String dbPassword = "database_password";
try{
conexion = (ConnectionImpl) DriverManager.getConnection(connectionPath, dbUser, dbPassword);
}catch(SQLException e){
System.err.println(e);
}
return conexion;
}
Remember to add the connector/J to the project referenced libraries.
In my case, the connector/J version is the 5.1.42. Maybe you will have to apply some changes to the connectionPath if you want to use a more modern version of the connector/J such as with the version 8.0.28.
In the file, remember to import the following resources:
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import com.mysql.jdbc.ConnectionImpl;
Hope this will be helpful.
Connection cn = DriverManager.getConnection("Host","user","pass");
Statement st = cn.createStatement("Ur Requet Sql");
int ret = st.execute();
The Simple Preparation example in the docs (https://www.npgsql.org/doc/prepare.html#simple-preparation) shows an example where parameters are set after the command is prepared.
var cmd = new NpgsqlCommand(...);
cmd.Parameters.Add("param", NpgsqlDbType.Integer);
cmd.Prepare();
// Set parameters
cmd.ExecuteNonQuery();
// And so on
Questions
How are the parameters set?
Is it possible to use AddWithValue instead of Add if the AddWithValue(String, NpgsqlDbType, Object) method which specifies NpgsqlDbType is used -- docs say "setting the value isn't support"?
How does this work if multiple statements exist in the same command?
This answer (https://stackoverflow.com/a/53268090/10984827) shows that multiple commands in a single string can be prepared together but it's not clear how this CommandText string is created.
Edit: I think I'm almost there but I'm not sure how to create and execute the batched the query string. Here's my naive attempt at building a batched query using a StringBuilder. This doesn't work. How do I do this correctly?
using System;
using System.Collections.Generic;
using System.Text;
using Npgsql;
using NpgsqlTypes;
class Model
{
public int value1 { get; }
public int value2 { get; }
public Model(int value1, int value2)
{
this.value1 = value1;
this.value2 = value2;
}
}
class Program
{
static void Main(string[] args)
{
var dataRows = new List<Model>();
dataRows.Add(new Model(3,2));
dataRows.Add(new Model(27,-10));
dataRows.Add(new Model(11,-11));
var connString = "Host=127.0.0.1;Port=5432;Username=postgres;Database=dbtest1";
// tabletest1
// ----------
// id SERIAL PRIMARY KEY
// , value1 INT NOT NULL
// , value2 INT NOT NULL
using (var conn = new NpgsqlConnection(connString))
{
conn.Open();
var cmd = new NpgsqlCommand();
cmd.Connection = conn;
cmd.CommandText = $"INSERT INTO tabletest1 (value1,value2) VALUES (#value1,#value2)";
var parameterValue1 = cmd.Parameters.Add("value1", NpgsqlDbType.Integer);
var parameterValue2 = cmd.Parameters.Add("value2", NpgsqlDbType.Integer);
cmd.Prepare();
var batchCommand = new StringBuilder();
foreach (var d in dataRows)
{
parameterValue1.Value = d.value1;
parameterValue2.Value = d.value2;
batchCommand.Append(cmd.CommandText);
batchCommand.Append(";");
}
Console.WriteLine(batchCommand.ToString());
// conn.ExecuteNonQuery(batchCommand.ToString());
}
}
}
1) Simply capture the NpgsqlParameter returned from Add(), and then set its Value property:
var p = cmd.Parameters.Add("p", NpgsqlDbType.Integer);
cmd.Prepare();
p.Value = 8;
cmd.ExecuteNonQuery();
2) You can use AddWithValue() in the same way, but if you're preparing the command in order to reuse it several times, that makes less sense. The idea is that you first add the parameter without a value, then prepare, then execute it several times, setting the value each time.
3) You can prepare a multi-statement command. As things work now, all statements in the command will share the same parameter list (which lives on NpgsqlCommand). So the same pattern holds: create your command with your SQL and parameters, prepare it, and then set parameter values and execute. Each individual statement within your command will run prepared, benefiting from the perf increase.
Here's an example with two-statement batching:
cmd.CommandText = "INSERT INTO tabletest1 (value1,value2) VALUES (#v1,#v2); INSERT INTO tabletest1 (value1, value2) VALUES (#v3,#v4)";
var v1 = cmd.Parameters.Add("v1", NpgsqlDbType.Integer);
var v2 = cmd.Parameters.Add("v2", NpgsqlDbType.Integer);
var v3 = cmd.Parameters.Add("v3", NpgsqlDbType.Integer);
var v4 = cmd.Parameters.Add("v4", NpgsqlDbType.Integer);
cmd.Prepare();
while (...) {
v1.Value = ...;
v2.Value = ...;
v3.Value = ...;
v4.Value = ...;
cmd.ExecuteNonQuery();
}
However, if the objective is to efficiently insert lots of data, consider using COPY instead - it will be faster than even batched inserts.
Finally, to complete the picture, for INSERT statements specifically you can include more than one row in a single statement:
INSERT INTO tabletest1 (value1, value2) VALUES (1,2), (3,4)
You can also again parameterize the actual values, and prepare this command. This is similar to batching two INSERT statements, and should be faster (although still slower than COPY).
In NpgSQL 6.0 there has been the addition of batching/pipelining.
Here is an updated example:
await using var connection = new NpgsqlConnection(connString);
await connection.OpenAsync();
var batch = new NpgsqlBatch(connection);
const int count = 10;
const string parameterName = "parameter";
for (int i = 0; i < count; i++)
{
var batchCommand = new NpgsqlBatchCommand($"SELECT #{parameterName} as value");
batchCommand.Parameters.Add(new NpgsqlParameter(parameterName, i));
batch.BatchCommands.Add(batchCommand);
}
await batch.PrepareAsync();
var results = new List<int>(count);
await using (var reader = await batch.ExecuteReaderAsync())
{
do
{
while (await reader.ReadAsync())
{
results.Add(await reader.GetFieldValueAsync<int>("value"));
}
} while (await reader.NextResultAsync());
}
Console.WriteLine(string.Join(", ", results));
Struggle with understanding C# & Npgsql as a beginner. Following code examples:
// Insert some data
using (var cmd = new NpgsqlCommand())
{ cmd.Connection = conn;
cmd.CommandText = "INSERT INTO data (some_field) VALUES (#p)";
cmd.Parameters.AddWithValue("p", "Hello world");
cmd.ExecuteNonQuery();
}
The syntax for more than one insert & update statement like this is clear so far:
cmd.CommandText = "INSERT INTO data (some_field) VALUES (#p);INSERT INTO data1...;INSERT into data2... and so on";
But what is the right solution for a loop which should handle one statement within.
This works not:
// Insert some data
using (var cmd = new NpgsqlCommand())
{
foreach(s in SomeStringCollectionOrWhatever)
{
cmd.Connection = conn;
cmd.CommandText = "INSERT INTO data (some_field) VALUES (#p)";
cmd.Parameters.AddWithValue("p", s);
cmd.ExecuteNonQuery();
}
}
It seems the values will be "concatenated" or remembered. I cannot see any possibility to "clear" the existing cmd-object.
My second solution would be to wrap the whole "using" block into the loop. But every cycle would create a new object. That seems ugly to me.
So what is the best solution for my problem?
To insert lots of rows efficiently, take a look at Npgsql's bulk copy feature - the API is more suitable (and more efficient) for inserting large numbers of rows than concatenating INSERT statements into a batch like you're trying to do.
If you want to rerun the same SQL with changing parameter values, you can do the following:
using (var cmd = new NpgsqlCommand("INSERT INTO data (some_field) VALUES (#p)", conn))
{
var p = new NpgsqlParameter("p", DbType.String); // Adjust DbType according to type
cmd.Parameters.Add(p);
cmd.Prepare(); // This is optional but will optimize the statement for repeated use
foreach(var s in SomeStringCollectionOrWhatever)
{
p.Value = s;
cmd.ExecuteNonQuery();
}
}
If you need lots of rows and performance is key then i would recommend Npgsql's bulk copy capability as #Shay mentioned. But if you are looking for quick way to do this without the bulk copy i would recommend to use Dapper.
Consider the example below.
Lets say you have a class called Event and a list of events to add.
List<Event> eventsToInsert = new List<Event>
{
new Event() { EventId = 1, EventName = "Bday1" },
new Event() { EventId = 2, EventName = "Bday2" },
new Event() { EventId = 3, EventName = "Bday3" }
};
The snippet that would add the list to the DB shown below.
var sqlInsert = "Insert into events( eventid, eventname ) values (#EventId, #EventName)";
using (IDbConnection conn = new NpgsqlConnection(cs))
{
conn.Open();
// Execute is an extension method supplied by Dapper
// This code will add all the entries in the eventsToInsert List and match up the values based on property name. Only caveat is that the property names of the POCO should match the placeholder names in the SQL Statement.
conn.Execute(sqlInsert, eventsToInsert);
// If we want to retrieve the data back into the list
List<Event> eventsAdded;
// This Dapper extension will return an Ienumerable, so i cast it to a List.
eventsAdded = conn.Query<Event>("Select * from events").ToList();
foreach( var row in eventsAdded)
{
Console.WriteLine($"{row.EventId} {row.EventName} was added");
}
}
-HTH
I am trying to get data using a SqlDataReader. When I look at the result, I do see the number of columns but rows are missing and I am seeing only blanks with "the enumeration yielded no results".
After spending much time and going through similar issues on the net I couldn't resolve my issue. Then I tried the same stored procedure but used the DataAdapter. Using a DataAdapter, all the rows were returned. I am not sure what is causing the issue. I tried to rewrite my methods differently but no avail.
public static SqlDataReader ExecuteDataReader(string connection, string storedProcedure)
{
using (var sqlCon = new SqlConnection(connection))
{
// sqlCon.Open();
var cmd = new SqlCommand(storedProcedure, sqlCon)
{
CommandType = CommandType.StoredProcedure
};
sqlCon.Open();
using (var reader = cmd.ExecuteReader())
{
var count = reader.FieldCount;
while (reader.Read())
{
for (var i = 0; i < count; i++)
{
Console.WriteLine(reader.GetValue(i));
}
}
}
//reader.Close();
return null; // for testing purpose
}
}
--stored procedure. (kept it simple)
Create PROC [dbo].GetTheData
As
select '1' AS one,'2' as two,'3' as three,'4' as four,'5'as five
in my opinion for dapper.query object there is a datareader, for dapper.Execute there is a ExectureNonQuery object. Correct me if i am wrong .
Can we use dapper for dataset which returns multiple tables?
No, there is not any built in support for DataSet, primarily because it seems largely redundant, but also because that isn't what dapper targets. But that doesn't mean it doesn't include an API for handling a query that selects multiple results; see QueryMultiple:
using (var multi = conn.QueryMultiple(sql, args))
{
var ids = multi.Read<int>().ToList();
var customers = multi.Read<Customer>().ToList();
dynamic someOtherRow = multi.Read().Single();
int qty = someOtherRow.Quantity, price = someOtherRow.Price;
}
Note that this API is forwards only (due to the nature of IDataReader etc) - basically, each Read / Read<T> etc maps to the next result grid in turn.
I might be late here but this is how I am doing the conversion of the IDataReader to a DataSet. Dapper returns a IDataReader when we use the ExecuteReaderAsync method. More information on this addition can be found here and here.
This is my attempt on this:
public async Task<DataSet> GetUserInformationOnUserId(int UserId)
{
var storedprocedure = "usp_getUserInformation";
var param = new DynamicParameters();
param.Add("#userId", UserId);
var list = await SqlMapper.ExecuteReaderAsync(_connectionFactory.GetEpaperDBConnection, storedprocedure, param, commandType: CommandType.StoredProcedure);
var dataset = ConvertDataReaderToDataSet(list);
return dataset;
}
And the ConvertDataReaderToDataSet will take in the IDataReader, you can use this method to convert the IReader to Dataset:
public DataSet ConvertDataReaderToDataSet(IDataReader data)
{
DataSet ds = new DataSet();
int i = 0;
while (!data.IsClosed)
{
ds.Tables.Add("Table" + (i + 1));
ds.EnforceConstraints = false;
ds.Tables[i].Load(data);
i++;
}
return ds;
}