Java/Database SQL JDBC/Key
Содержание
Demo Get Generated Keys MySQL
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
public class DemoGetGeneratedKeysMySQL {
public static Connection getConnection() throws Exception {
String driver = "org.gjt.mm.mysql.Driver";
String url = "jdbc:mysql://localhost/databaseName";
String username = "root";
String password = "root";
Class.forName(driver);
Connection conn = DriverManager.getConnection(url, username, password);
return conn;
}
public static void main(String[] args)throws Exception {
Connection conn = getConnection();
Statement stmt = null;
ResultSet rs = null;
try {
conn = getConnection();
stmt = conn.createStatement();
stmt.executeUpdate("insert into animals_table (name) values("newName")");
rs = stmt.getGeneratedKeys();
while (rs.next()) {
ResultSetMetaData rsMetaData = rs.getMetaData();
int columnCount = rsMetaData.getColumnCount();
for (int i = 1; i <= columnCount; i++) {
String key = rs.getString(i);
System.out.println("key " + i + " is " + key);
}
}
} catch (Exception e) {
e.printStackTrace();
System.exit(1);
} finally {
try {
rs.close();
stmt.close();
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
Get Foreign Keys
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class Main {
public static void main(String[] args) throws Exception {
Connection conn = getMySqlConnection();
System.out.println("Got Connection.");
Statement st = conn.createStatement();
st.executeUpdate("drop table survey;");
st.executeUpdate("create table survey (id int,name varchar(30));");
st.executeUpdate("insert into survey (id,name ) values (1,"nameValue")");
ResultSet rs = null;
DatabaseMetaData meta = conn.getMetaData();
// The Oracle database stores its table names as Upper-Case,
// if you pass a table name in lowercase characters, it will not work.
// MySQL database does not care if table name is uppercase/lowercase.
//
rs = meta.getExportedKeys(conn.getCatalog(), null, "survey");
while (rs.next()) {
String fkTableName = rs.getString("FKTABLE_NAME");
String fkColumnName = rs.getString("FKCOLUMN_NAME");
int fkSequence = rs.getInt("KEY_SEQ");
System.out.println("getExportedKeys(): fkTableName="+fkTableName);
System.out.println("getExportedKeys(): fkColumnName="+fkColumnName);
System.out.println("getExportedKeys(): fkSequence="+fkSequence);
}
st.close();
conn.close();
}
private static Connection getHSQLConnection() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
System.out.println("Driver Loaded.");
String url = "jdbc:hsqldb:data/tutorial";
return DriverManager.getConnection(url, "sa", "");
}
public static Connection getMySqlConnection() throws Exception {
String driver = "org.gjt.mm.mysql.Driver";
String url = "jdbc:mysql://localhost/demo2s";
String username = "oost";
String password = "oost";
Class.forName(driver);
Connection conn = DriverManager.getConnection(url, username, password);
return conn;
}
public static Connection getOracleConnection() throws Exception {
String driver = "oracle.jdbc.driver.OracleDriver";
String url = "jdbc:oracle:thin:@localhost:1521:caspian";
String username = "mp";
String password = "mp2";
Class.forName(driver); // load Oracle driver
Connection conn = DriverManager.getConnection(url, username, password);
return conn;
}
}
Get Imported Keys
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class Main {
public static void main(String[] args) throws Exception {
Connection conn = getMySqlConnection();
System.out.println("Got Connection.");
Statement st = conn.createStatement();
st.executeUpdate("drop table survey;");
st.executeUpdate("create table survey (id int,name varchar(30));");
st.executeUpdate("insert into survey (id,name ) values (1,"nameValue")");
ResultSet rs = null;
DatabaseMetaData meta = conn.getMetaData();
// The Oracle database stores its table names as Upper-Case,
// if you pass a table name in lowercase characters, it will not work.
// MySQL database does not care if table name is uppercase/lowercase.
//
rs = meta.getImportedKeys(conn.getCatalog(), null, "survey");
while (rs.next()) {
String fkTableName = rs.getString("FKTABLE_NAME");
String fkColumnName = rs.getString("FKCOLUMN_NAME");
int fkSequence = rs.getInt("KEY_SEQ");
System.out.println("getExportedKeys(): fkTableName="+fkTableName);
System.out.println("getExportedKeys(): fkColumnName="+fkColumnName);
System.out.println("getExportedKeys(): fkSequence="+fkSequence);
}
st.close();
conn.close();
}
private static Connection getHSQLConnection() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
System.out.println("Driver Loaded.");
String url = "jdbc:hsqldb:data/tutorial";
return DriverManager.getConnection(url, "sa", "");
}
public static Connection getMySqlConnection() throws Exception {
String driver = "org.gjt.mm.mysql.Driver";
String url = "jdbc:mysql://localhost/demo2s";
String username = "oost";
String password = "oost";
Class.forName(driver);
Connection conn = DriverManager.getConnection(url, username, password);
return conn;
}
public static Connection getOracleConnection() throws Exception {
String driver = "oracle.jdbc.driver.OracleDriver";
String url = "jdbc:oracle:thin:@localhost:1521:caspian";
String username = "mp";
String password = "mp2";
Class.forName(driver); // load Oracle driver
Connection conn = DriverManager.getConnection(url, username, password);
return conn;
}
}
Get Primary Key Column From A Table
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class Main {
public static void main(String[] args) throws Exception {
Connection conn = getHSQLConnection();
System.out.println("Got Connection.");
Statement st = conn.createStatement();
st.executeUpdate("create table survey (id int,name varchar, PRIMARY KEY (id) );");
st.executeUpdate("insert into survey (id,name ) values (1,"nameValue")");
ResultSet rs = null;
DatabaseMetaData meta = conn.getMetaData();
// The Oracle database stores its table names as Upper-Case,
// if you pass a table name in lowercase characters, it will not work.
// MySQL database does not care if table name is uppercase/lowercase.
//
rs = meta.getPrimaryKeys(null, null, "survey");
java.util.List list = new java.util.ArrayList();
while (rs.next()) {
String columnName = rs.getString("COLUMN_NAME");
System.out.println("getPrimaryKeys(): columnName=" + columnName);
}
st.close();
conn.close();
}
private static Connection getHSQLConnection() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
System.out.println("Driver Loaded.");
String url = "jdbc:hsqldb:data/tutorial";
return DriverManager.getConnection(url, "sa", "");
}
public static Connection getMySqlConnection() throws Exception {
String driver = "org.gjt.mm.mysql.Driver";
String url = "jdbc:mysql://localhost/octopus";
String username = "root";
String password = "root";
Class.forName(driver); // load MySQL driver
Connection conn = DriverManager.getConnection(url, username, password);
return conn;
}
public static Connection getOracleConnection() throws Exception {
String driver = "oracle.jdbc.driver.OracleDriver";
String url = "jdbc:oracle:thin:@localhost:1521:caspian";
String username = "mp";
String password = "mp2";
Class.forName(driver); // load Oracle driver
Connection conn = DriverManager.getConnection(url, username, password);
return conn;
}
}