Retrieve column names from java.sql.ResultSet

Question

With java.sql.ResultSet is there a way to get a column's name as a String by using the column's index? I had a look through the API doc but I can't find anything.

Answer 1

ResultSet rsTst = hiSession.connection().prepareStatement(queryStr).executeQuery(); 
ResultSetMetaData meta = rsTst.getMetaData();
int columnCount = meta.getColumnCount();
// The column count starts from 1

String nameValuePair = "";
while (rsTst.next()) {
    for (int i = 1; i < columnCount + 1; i++ ) {
        String name = meta.getColumnName(i);
        // Do stuff with name

        String value = rsTst.getString(i); //.getObject(1);
        nameValuePair = nameValuePair + name + "=" +value + ",";
        //nameValuePair = nameValuePair + ", ";
    }
    nameValuePair = nameValuePair+"||" + "\t";
}

Answer 2

In addition to the above answers, if you're working with a dynamic query and you want the column names but do not know how many columns there are, you can use the ResultSetMetaData object to get the number of columns first and then cycle through them.

Ammending Brian's code:

ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM TABLE2");
ResultSetMetaData rsmd = rs.getMetaData();
int columnCount = rsmd.getColumnCount();

// The column count starts from 1
for (int i = 1; i <= columnCount; i++ ) {
  String name = rsmd.getColumnName(i);
  // Do stuff with name
}

Answer 3

SQLite 3

Using getMetaData();

DatabaseMetaData md = conn.getMetaData();
ResultSet rset = md.getColumns(null, null, "your_table_name", null);

System.out.println("your_table_name");
while (rset.next())
{
    System.out.println("\t" + rset.getString(4));
}

EDIT: This works with PostgreSQL as well

Answer 4

import java.sql.*;

public class JdbcGetColumnNames {

    public static void main(String args[]) {
        Connection con = null;
        Statement st = null;
        ResultSet rs = null;

        try {
            Class.forName("com.mysql.jdbc.Driver");
            con = DriverManager.getConnection(
                    "jdbc:mysql://localhost:3306/komal", "root", "root");

            st = con.createStatement();

            String sql = "select * from person";
            rs = st.executeQuery(sql);
            ResultSetMetaData metaData = rs.getMetaData();

            int rowCount = metaData.getColumnCount();

            System.out.println("Table Name : " + metaData.getTableName(2));
            System.out.println("Field  \tDataType");

            for (int i = 0; i < rowCount; i++) {
                System.out.print(metaData.getColumnName(i + 1) + "  \t");
                System.out.println(metaData.getColumnTypeName(i + 1));
            }
        } catch (Exception e) {
            System.out.println(e);
        }
    }
}

Table Name : person Field DataType id VARCHAR cname VARCHAR dob DATE