Java/Database SQL JDBC/ResultSetMetaData

Create Custom RowSet MetaData

 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
import java.sql.Types;
import javax.sql.RowSetMetaData;
import javax.sql.rowset.CachedRowSet;
import javax.sql.rowset.RowSetMetaDataImpl;
import com.sun.rowset.CachedRowSetImpl;
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);");
    st.executeUpdate("create view surveyView as (select * from survey);");
    st.executeUpdate("insert into survey (id,name ) values (1,"nameValue")");
    st.executeUpdate("insert into survey (id,name ) values (2,"anotherValue")");    
    
    CachedRowSet crs = null;
    RowSetMetaData rsMD = new RowSetMetaDataImpl();
    rsMD.setColumnCount(2);
    rsMD.setColumnName(1, "id");
    rsMD.setColumnType(1, Types.VARCHAR);
    rsMD.setColumnName(2, "name");
    rsMD.setColumnType(2, Types.VARCHAR);
    // sets the designated column"s table name, if any, to the given String.
    rsMD.setTableName(1, "survey");
    rsMD.setTableName(2, "survey");
    // use a custom made RowSetMetaData object for CachedRowSet object
    crs = new CachedRowSetImpl();
    crs.setMetaData(rsMD);
    crs.moveToInsertRow();
    crs.updateString(1, "1111");
    crs.updateString(2, "alex");
    crs.insertRow();
    crs.moveToInsertRow();
    crs.updateString(1, "2222");
    crs.updateString(2, "jane");
    crs.insertRow();
    // if you want to commit changes from a CachedRowSet
    // object to your desired datasource, then you must
    // create a Connection object.
    //
    //conn = getHSQLConnection();
    // moves the cursor to the remembered cursor position, usually
    // the current row. This method has no effect if the cursor is
    // not on the insert row.
    crs.moveToCurrentRow();
    // when the method acceptChanges() is executed, the CachedRowSet
    // object"s writer, a RowSetWriterImpl object, is called behind the
    // scenes to write the changes made to the rowset to the underlying
    // data source. The writer is implemented to make a connection to
    // the data source and write updates to it.
    crs.acceptChanges(conn);
    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 ResultSet Metadata

 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
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")");
    st = conn.createStatement();
    ResultSet rs = st.executeQuery("SELECT * FROM survey");
    ResultSetMetaData rsMetaData = rs.getMetaData();
    int numberOfColumns = rsMetaData.getColumnCount();
    System.out.println("resultSet MetaData column Count=" + numberOfColumns);
    for (int i = 1; i <= numberOfColumns; i++) {
      System.out.println("column MetaData ");
      System.out.println("column number " + i);
      // indicates the designated column"s normal maximum width in
      // characters
      System.out.println(rsMetaData.getColumnDisplaySize(i));
      // gets the designated column"s suggested title
      // for use in printouts and displays.
      System.out.println(rsMetaData.getColumnLabel(i));
      // get the designated column"s name.
      System.out.println(rsMetaData.getColumnName(i));
      // get the designated column"s SQL type.
      System.out.println(rsMetaData.getColumnType(i));
      // get the designated column"s SQL type name.
      System.out.println(rsMetaData.getColumnTypeName(i));
      // get the designated column"s class name.
      System.out.println(rsMetaData.getColumnClassName(i));
      // get the designated column"s table name.
      System.out.println(rsMetaData.getTableName(i));
      // get the designated column"s number of decimal digits.
      System.out.println(rsMetaData.getPrecision(i));
      // gets the designated column"s number of
      // digits to right of the decimal point.
      System.out.println(rsMetaData.getScale(i));
      // indicates whether the designated column is
      // automatically numbered, thus read-only.
      System.out.println(rsMetaData.isAutoIncrement(i));
      // indicates whether the designated column is a cash value.
      System.out.println(rsMetaData.isCurrency(i));
      // indicates whether a write on the designated
      // column will succeed.
      System.out.println(rsMetaData.isWritable(i));
      // indicates whether a write on the designated
      // column will definitely succeed.
      System.out.println(rsMetaData.isDefinitelyWritable(i));
      // indicates the nullability of values
      // in the designated column.
      System.out.println(rsMetaData.isNullable(i));
      // Indicates whether the designated column
      // is definitely not writable.
      System.out.println(rsMetaData.isReadOnly(i));
      // Indicates whether a column"s case matters
      // in the designated column.
      System.out.println(rsMetaData.isCaseSensitive(i));
      // Indicates whether a column"s case matters
      // in the designated column.
      System.out.println(rsMetaData.isSearchable(i));
      // indicates whether values in the designated
      // column are signed numbers.
      System.out.println(rsMetaData.isSigned(i));
      // Gets the designated column"s table"s catalog name.
      System.out.println(rsMetaData.getCatalogName(i));
      // Gets the designated column"s table"s schema name.
      System.out.println(rsMetaData.getSchemaName(i));
    }
    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 Table Name From ResultSet Metadata

 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
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")");
    st = conn.createStatement();
    ResultSet rs = st.executeQuery("SELECT * FROM survey");
    ResultSetMetaData rsMetaData = rs.getMetaData();
    int numberOfColumns = rsMetaData.getColumnCount();
    System.out.println("resultSet MetaData column Count=" + numberOfColumns);
    for (int i = 1; i <= numberOfColumns; i++) {
      System.out.println("column MetaData ");
      System.out.println("column number " + i);

      // get the designated column"s table name.
      System.out.println(rsMetaData.getTableName(i));
    }
    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 Table Schema Name From ResultSet Metadata

 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
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")");
    st = conn.createStatement();
    ResultSet rs = st.executeQuery("SELECT * FROM survey");
    ResultSetMetaData rsMetaData = rs.getMetaData();
    int numberOfColumns = rsMetaData.getColumnCount();
    System.out.println("resultSet MetaData column Count=" + numberOfColumns);
    for (int i = 1; i <= numberOfColumns; i++) {
      System.out.println("column MetaData ");
      System.out.println("column number " + i);
      // Gets the designated column"s table"s schema name.
      System.out.println(rsMetaData.getSchemaName(i));
    }
    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;
  }
}

Getting the Column Names in a Result Set

  
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Main {
  public static void main(String[] argv) throws Exception {
    String driverName = "com.jnetdirect.jsql.JSQLDriver";
    Class.forName(driverName);
    String serverName = "127.0.0.1";
    String portNumber = "1433";
    String mydatabase = serverName + ":" + portNumber;
    String url = "jdbc:JSQLConnect://" + mydatabase;
    String username = "username";
    String password = "password";
    Connection connection = DriverManager.getConnection(url, username, password);
    Statement stmt = connection.createStatement();
    ResultSet rs = stmt.executeQuery("SELECT * FROM mysql_all_table");
    ResultSetMetaData rsmd = rs.getMetaData();
    int numColumns = rsmd.getColumnCount();
    for (int i = 1; i < numColumns + 1; i++) {
      String columnName = rsmd.getColumnName(i);
      String tableName = rsmd.getTableName(i);
    }
  }
}

ResultSet Metadata from Oracle Driver

  
import java.math.BigDecimal;
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 RSMetaData {
  public static void main(String[] args) throws Exception {
    String driver = "oracle.jdbc.driver.OracleDriver";
    Class.forName(driver).newInstance();
    String jdbcUrl = "jdbc:oracle:thin:@localhost:1521:ORCL";
    Connection conn = DriverManager.getConnection(jdbcUrl, "yourName", "mypwd");
    Statement stmt = conn.createStatement();
    ResultSet rs = stmt.executeQuery("SELECT * FROM Employees");
    printColumnInfo(rs);
    printColumnNames(rs);
    processRs(rs);
    rs = stmt.executeQuery("SELECT * FROM Location");
    printColumnInfo(rs);
    printColumnNames(rs);
    processRs(rs);
    conn.close();
  }
  public static void processRs(ResultSet rs) throws SQLException {
    ResultSetMetaData rmd = rs.getMetaData();
    while (rs.next()) {
      for (int col = 1; col <= rmd.getColumnCount(); col++)
        getData(rs, rmd.getColumnType(col), col);
    }
  }
  public static void printColumnNames(ResultSet rs) throws SQLException {
    ResultSetMetaData rmd = rs.getMetaData();
    for (int col = 1; col <= rmd.getColumnCount(); col++)
      System.out.println(rmd.getColumnName(col) + " ");
  }
  public static void getData(ResultSet rs, int type, int colIdx) throws SQLException {
    switch (type) {
    case java.sql.Types.CHAR:
    case java.sql.Types.VARCHAR:
      System.out.println(rs.getString(colIdx));
      break;
    case java.sql.Types.INTEGER:
      int i = rs.getInt(colIdx);
      System.out.println(i);
      break;
    case java.sql.Types.NUMERIC:
      BigDecimal bd = rs.getBigDecimal(colIdx);
      System.out.println(bd.toString());
      break;
    case java.sql.Types.TIMESTAMP:
    case java.sql.Types.DATE:
      java.sql.Date d = rs.getDate(colIdx);
      System.out.println(d.toString());
      break;
    }
  }
  public static void printColumnInfo(ResultSet rs) throws SQLException {
    ResultSetMetaData rsmd = rs.getMetaData();
    int cols = rsmd.getColumnCount();
    for (int colIdx = 1; colIdx <= cols; colIdx++) {
      String name = rsmd.getColumnName(colIdx);
      int type = rsmd.getColumnType(colIdx);
      String typeName = rsmd.getColumnTypeName(colIdx);
      System.out.println(name + ", " + type + ", " + typeName);
    }
  }
}