Jdbc - ResultSetMetaData in java - Retrieve table column name and datatype


  • java.sql.ResultSetMetaData is an interface.
  • java.sql.ResultSetMetaData’s object can be used to get information about the types and properties of the columns in a java.sql.ResultSet object.
  • java.sql.ResultSetMetaData extends java.sql.Wrapper.
  • ResultSetMetaData important methods -
getColumnCount = To find out total number of columns in table
getColumnName =  Display table's column type
getColumnTypeName=  Display table's column type



--Before executing java program execute these database scripts  >
create table EMPLOYEE(ID number(4),NAME varchar2(22));
insert into EMPLOYEE values(1, 'ankit');
insert into EMPLOYEE values(2, 'rohit');
insert into EMPLOYEE values(3, 'amy');
commit;

--If table already exists then execute the DROP command >
drop table EMPLOYEE;


EMPLOYEE table will look like this >


Also read : PreparedStatement BATCH - using executeUpdate methods - INSERT and DELETE

Full Programs JDBC- How to use ResultSetMetaData
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
/** Copyright (c), AnkitMittal JavaMadeSoEasy.com */
public class ResultSetMetaDataTest {
   public static void main(String... arg) {
          Connection con = null;
          PreparedStatement prepStmt = null;
          ResultSet rs = null;                 
          try {
                 // registering Oracle driver class
                 Class.forName("oracle.jdbc.driver.OracleDriver");
                 // getting connection
                 con = DriverManager.getConnection(
                              "jdbc:oracle:thin:@localhost:1521:orcl",
                              "ankit", "Oracle123");
                 System.out.println("Connection established successfully!");
                
                
                
                 prepStmt = con.prepareStatement("select * from EMPLOYEE");
                 //execute select query
                 //Obtain ResultSet
                 rs = prepStmt.executeQuery();
                
                 ResultSetMetaData rsmd = rs.getMetaData();
                 int totalNumberOfColumnsInTable = rsmd.getColumnCount();
                 System.out.println("\nTotal number of columns in table = "
                              + totalNumberOfColumnsInTable);
                 System.out.println("\nDisplay table's column name and column type - ");
                 for(int i=1; i<=totalNumberOfColumnsInTable; i++){
                       System.out.println( " Column no = "+ i  +
                                     ", column name = " + rsmd.getColumnName(i) +
                                     ", column type = " + rsmd.getColumnTypeName(i));
                 }
                 rs.close();
  
                
          } catch (ClassNotFoundException e) {
                 e.printStackTrace();
          } catch (SQLException e) {
                 e.printStackTrace();
          }
          finally{
                 try {
                       if(rs!=null) rs.close(); //close resultSet
                       if(prepStmt!=null) prepStmt.close(); //close PreparedStatement
                       if(con!=null) con.close(); // close connection
                 } catch (SQLException e) {
                       e.printStackTrace();
                 }
          }
   }
}
/*OUTPUT
Connection established successfully!
Total number of columns in table = 2
Display table's column name and column type -
Column no = 1, column name = ID, column type = NUMBER
Column no = 2, column name = NAME, column type = VARCHAR2
*/




RELATED LINKS>

JDBC- Batch PreparedStatement example- Execute INSERT query(DML command) using PreparedStatement's addBatch() and executeBatch() methods in java


12 Differences between Statement, PreparedStatement and CallableStatement in java


JDBC- Calling Oracle database STORED PROCEDURE and pass its IN parameter from java - CallableStatement example in java

JDBC- Calling Oracle database STORED PROCEDURE- OUT parameter - CallableStatement example in java

JDBC- Calling Oracle database STORED PROCEDURE- IN OUT parameter - CallableStatement example in java


JDBC- Calling Oracle database FUNCTION - CallableStatement example in java


Labels: Core Java JDBC
eEdit
Must read for you :