MySQL load Data with "true" in it - java

is it possible to load only the strings from my database to my server, which have "true" in it? E.g.: It should load"a.b.e.true" but not "a.b.e" When yes, how can I do that? I am using Java.

Yes; it would be slow, but your query would be something like this:
SELECT string_column FROM table_name WHERE string_column LIKE '%true%'
If you also want to match on "TRUE", then you'd replace LIKE with ILIKE (which is case-insensitive).
Below is some example code for getting this data [Source]
// Assuming you already have a Connection object named con
Statement stmt = null;
List<String> toRet = new ArrayList<String>();
String query = "SELECT string_column FROM table_name WHERE string_column LIKE '%true%'";
try
{
stmt = con.createStatement();
ResultSet rs = stmt.executeQuery(query);
while(rs.next())
{
toRet.add(rs.getString("string_column"));
}
}
catch(SQLException e)
{
e.printStackTrace();
}
finally
{
if(stmt != null)
{
stmt.close();
}
}

Related

How do I get the last inserted primary key? [duplicate]

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();

How to perform one to one table INSERT query [duplicate]

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();

Assign to string instead of resultset for jdbc query

I need to get the output of a jdbc query, but wherever I google, it returns a resultset. But, its just a single row. Here is my query
ResultSet rsLocationId = null;
rsLocationId = stmtLocation.executeQuery("SELECT apmcid FROM userbusinesstoapmc WHERE userbusinessid='"+userBusinessKey+"'");
It should return a single record as a string. How can I convert it? Any ideas would be greatly appreciated.
I suggest you use PreparedStatement and bind the parameter, currently you are vulnerable to SQL Injection attacks.
PreparedStatement ps = null;
ResultSet rs = null;
String result = null;
final String sql = "SELECT apmcid FROM userbusinesstoapmc "
+ "WHERE userbusinessid=?";
try {
ps = conn.prepareStatement(sql);
ps.setString(1, userBusinessKey);
rs = ps.executeQuery();
if (rs.next()) {
result = rs.getString("apmcid");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (ps != null) {
try {
ps.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
you can try like this
ResultSet rsLocationId = null;String result="";
rsLocationId = stmtLocation.executeQuery("SELECT apmcid FROM userbusinesstoapmc WHERE userbusinessid='"+userBusinessKey+"'");
if(rsLocationId.next())
{
result=rsLocationId.getString('apmcid');
}
Even though your particular query only returns a single column, presumably some CHAR type if you expect the result to be a String, the executeQuery method returns a result set object, not a String object. So, you have to process the result set to get your String data. SpringLearner has provided a good example of how to do this.

Can prepareStatement do the same thing like Statement?

My DB is Oracle.
I know Statement can mix SQL sentences(insert or delete or update) into one single batch. Here is my code.
DBConnection db = new DBConnection();
Connection c = db.getConn();
Statement s = null ;
try
{
String sql = "insert into t1(id, name) values ('10', 'apple')";
String sql1 = "insert into t1(id, name) values ('14', 'pie')";
String sql2 = "delete from t1 where id = '10'";
s = c.createStatement();
s.addBatch(sql);
s.addBatch(sql1);
s.addBatch(sql2);
int[] re = s.executeBatch();...
My question is can PreparedStatement do this? and how?
You can create a batch by PreparedStatement.addBatch() and you can execute it by PreparedStatement.executeBatch
For more about PreparedStatement you can look into documentation
Now if i am not wrong you want to do something like this:
public void save(List<Entity> elements) throws SQLException {
Connection connection = null;
PreparedStatement statement = null;
try {
connection = database.getConnection();
statement = connection.prepareStatement(SQL_INSERT);
for (int i = 0; i < elements.size(); i++) {
Element element= elements.get(i);
statement.setString(1, element.getProperty1());
statement.setString(2, element.getProperty2());
.....
statement.addBatch();
if ((i + 1) % 200 == 0) {
statement.executeBatch(); // Execute every 200 items.
}
}
statement.executeBatch();
} finally {
if (statement != null) try { statement.close(); } catch (SQLException e) { //}
if (connection != null) try { connection.close(); } catch (SQLException e) {//}
}
}
In this case i am executing every 200 items, if you wish you can set your own. But do test it because it also depends on drivers limitation on batch operations.
Statement:
Use for general-purpose access to your database. Useful when you are using static SQL statements at runtime. The Statement interface cannot accept parameters.
PreparedStatement:
Use when you plan to use the SQL statements many times. The PreparedStatement interface accepts input parameters at runtime.
CallableStatement:
Use when you want to access database stored procedures. The CallableStatement interface can also accept runtime input parameters.

Java - Getting Data from MySQL database

I've connected to a MySQL database, which contains four fields (the first of which being an ID, the latter ones each containing varchar strings).
I am trying to get the last row of the database and retrieve the contents of the fields so that I can set them to variables (an int and three strings) and use them later.
So far, I have the bare minimum to make the connection, where do I go from here? As you can see I have tried to write a SQL statement to get the last row but it's all gone wrong from there and I don't know how to split it into the separate fields.
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection("jdbc:mysql://localhost/t", "", "");
Statement st = con.createStatement();
String sql = ("SELECT * FROM posts ORDER BY id DESC LIMIT 1;");
st.getResultSet().getRow();
con.close();
Here you go :
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection("jdbc:mysql://localhost/t", "", "");
Statement st = con.createStatement();
String sql = ("SELECT * FROM posts ORDER BY id DESC LIMIT 1;");
ResultSet rs = st.executeQuery(sql);
if(rs.next()) {
int id = rs.getInt("first_column_name");
String str1 = rs.getString("second_column_name");
}
con.close();
In rs.getInt or rs.getString you can pass column_id starting from 1, but i prefer to pass column_name as its more informative as you don't have to look at database table for which index is what column.
UPDATE : rs.next
boolean next()
throws SQLException
Moves the cursor froward one row from its current position. A
ResultSet cursor is initially positioned before the first row; the
first call to the method next makes the first row the current row; the
second call makes the second row the current row, and so on.
When a call to the next method returns false, the cursor is positioned
after the last row. Any invocation of a ResultSet method which
requires a current row will result in a SQLException being thrown. If
the result set type is TYPE_FORWARD_ONLY, it is vendor specified
whether their JDBC driver implementation will return false or throw an
SQLException on a subsequent call to next.
If an input stream is open for the current row, a call to the method
next will implicitly close it. A ResultSet object's warning chain is
cleared when a new row is read.
Returns:
true if the new current row is valid; false if there are no more rows Throws:
SQLException - if a database access error occurs or this method is called on a closed result set
reference
Something like this would do:
public static void main(String[] args) {
Connection con = null;
Statement st = null;
ResultSet rs = null;
String url = "jdbc:mysql://localhost/t";
String user = "";
String password = "";
try {
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection(url, user, password);
st = con.createStatement();
rs = st.executeQuery("SELECT * FROM posts ORDER BY id DESC LIMIT 1;");
if (rs.next()) {//get first result
System.out.println(rs.getString(1));//coloumn 1
}
} catch (SQLException ex) {
Logger lgr = Logger.getLogger(Version.class.getName());
lgr.log(Level.SEVERE, ex.getMessage(), ex);
} finally {
try {
if (rs != null) {
rs.close();
}
if (st != null) {
st.close();
}
if (con != null) {
con.close();
}
} catch (SQLException ex) {
Logger lgr = Logger.getLogger(Version.class.getName());
lgr.log(Level.WARNING, ex.getMessage(), ex);
}
}
}
you can iterate over the results with a while like this:
while(rs.next())
{
System.out.println(rs.getString("Colomn_Name"));//or getString(1) for coloumn 1 etc
}
There are many other great tutorial out there like these to list a few:
http://www.vogella.com/articles/MySQLJava/article.html
http://www.java-samples.com/showtutorial.php?tutorialid=9
As for your use of Class.forName("com.mysql.jdbc.Driver").newInstance(); see JDBC connection- Class.forName vs Class.forName().newInstance? which shows how you can just use Class.forName("com.mysql.jdbc.Driver") as its not necessary to initiate it yourself
References:
http://zetcode.com/databases/mysqljavatutorial/
This should work, I think...
ResultSet results = st.executeQuery(sql);
if(results.next()) { //there is a row
int id = results.getInt(1); //ID if its 1st column
String str1 = results.getString(2);
...
}
Easy Java method to get data from MySQL table:
/*
* CREDIT : WWW.CODENIRVANA.IN
*/
String Data(String query){
String get=null;
try{
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = (Connection)DriverManager.getConnection
("jdbc:mysql://localhost:3306/mysql","root","password");
Statement stmt = (Statement) con.createStatement();
ResultSet rs=stmt.executeQuery(query);
if (rs.next())
{
get = rs.getString("");
}
}
catch(Exception e){
JOptionPane.showMessageDialog (this, e.getMessage());
}
return get;
}
Here is what I just did right now:
import java.sql.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import com.sun.javafx.runtime.VersionInfo;
public class ConnectToMySql {
public static ConnectBean dataBean = new ConnectBean();
public static void main(String args[]) {
getData();
}
public static void getData () {
try {
Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/mynewpage",
"root", "root");
// here mynewpage is database name, root is username and password
Statement stmt = con.createStatement();
System.out.println("stmt " + stmt);
ResultSet rs = stmt.executeQuery("select * from carsData");
System.out.println("rs " + rs);
int count = 1;
while (rs.next()) {
String vehicleType = rs.getString("VHCL_TYPE");
System.out.println(count +": " + vehicleType);
count++;
}
con.close();
} catch (Exception e) {
Logger lgr = Logger.getLogger(VersionInfo.class.getName());
lgr.log(Level.SEVERE, e.getMessage(), e);
System.out.println(e.getMessage());
}
}
}
The Above code will get you the first column of the table you have.
This is the table which you might need to create in your MySQL database
CREATE TABLE
carsData
(
VHCL_TYPE CHARACTER(10) NOT NULL,
);
First, Download MySQL connector jar file, This is the latest jar file as of today [mysql-connector-java-8.0.21].
Add the Jar file to your workspace [build path].
Then Create a new Connection object from the DriverManager class, so you could use this Connection object to execute queries.
Define the database name, userName, and Password for your connection.
Use the resultSet to get the data based one the column name from your database table.
Sample code is here:
public class JdbcMySQLExample{
public static void main(String[] args) {
String url = "jdbc:mysql://localhost:3306/YOUR_DB_NAME?useSSL=false";
String user = "root";
String password = "root";
String query = "SELECT * from YOUR_TABLE_NAME";
try (Connection con = DriverManager.getConnection(url, user, password);
Statement st = con.createStatement();
ResultSet rs = st.executeQuery(query)) {
if (rs.next()) {
System.out.println(rs.getString(1));
}
} catch (SQLException ex) {
System.out.println(ex);
}
}

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