(3), (4)에서는...
absolute를 이용하여 특정 위치를 결과를 뽑아서 사용할 경우의 속도 비교입니다.
5만건의 데이터를 쿼리한 것에서... 1001번째부터 1100까지 100개의 값을
추출하는 소스 입니다.
=============================================
while에서 뽑아오는 소스
--------------------------------------------------------------------------------
import java.sql.*;
import java.util.Vector;
public class DBTest6 {
Vector result = new Vector();
public void init() {
long start_full = System.currentTimeMillis();
String musician, music_subject, music_year, music_write, music_compose = null;
Connection conn = null;
Statement stmt = null;
try {
Class.forName("org.gjt.mm.mysql.Driver");
}catch (ClassNotFoundException ex) {
System.err.println("ClassNotFoundException: " + ex.getMessage());
}
try{
conn = DriverManager.getConnection("jdbc:mysql://localhost/music","music","music");
if(conn != null) {
stmt = conn.createStatement();
long start = System.currentTimeMillis();
ResultSet rst = stmt.executeQuery("select musician, music_subject, music_year, music_write, music_compose from musictest");
long end = System.currentTimeMillis();
double res1 = (double)(end - start) / 1000;
//System.out.println("start1 : "+start);
//System.out.println("end2 : "+end);
System.out.println("res1 : "+res1+"초");
long start2 = System.currentTimeMillis();
while(rst.next()) {
musician = rst.getString(1);
music_subject = rst.getString(2);
music_year = rst.getString(3);
music_write = rst.getString(4);
music_compose = rst.getString(4);
Vector row = new Vector();
row.add(musician);
row.add(music_subject);
row.add(music_year);
row.add(music_write);
row.add(music_compose);
result.add(row);
}
conn.close();
long end2 = System.currentTimeMillis();
double res2 = (double)(end2 - start2) / 1000;
System.out.println("res2 : "+res2+"초");
}
}catch(Exception e) {
e.printStackTrace();
}finally {
if ( stmt != null ) try{stmt.close();}catch(Exception e){}
if ( conn != null ) try{conn.close();}catch(Exception e){}
}
long end_full = System.currentTimeMillis();
double res_full = (double)(end_full - start_full) / 1000;
System.out.println("res_full : "+res_full+"초");
}
public Vector getResult(){
return result;
}
public static void main(String[] args) {
DBTest6 db = new DBTest6();
db.init();
Vector result = db.getResult();
long start = System.currentTimeMillis();
for(int i=1000; i < 1100; i++){
Vector row = (Vector)result.get(i);
String musician = (String)row.get(0);
String music_subject = (String)row.get(1);
String music_year = (String)row.get(2);
String music_write = (String)row.get(3);
String music_compose = (String)row.get(4);
System.out.println(musician +" : "+ music_subject + " : "+ music_year + " : "+ music_write + " : "+music_compose);
}
long end = System.currentTimeMillis();
double res2 = (double)(end - start) / 1000;
System.out.println("res3 : "+res2+"초");
}
}
---------------------------------------------------------------------------
absolute를 써서 뽑아오는 경우
---------------------------------------------------------------------------
import java.sql.*;
import java.util.Vector;
public class DBTest5 {
Vector result = new Vector();
public void init() {
long start_full = System.currentTimeMillis();
String musician, music_subject, music_year, music_write, music_compose = null;
Connection conn = null;
Statement stmt = null;
try {
Class.forName("org.gjt.mm.mysql.Driver");
}catch (ClassNotFoundException ex) {
System.err.println("ClassNotFoundException: " + ex.getMessage());
}
try{
conn = DriverManager.getConnection("jdbc:mysql://localhost/music","music","music");
if(conn != null) {
stmt = conn.createStatement();
long start = System.currentTimeMillis();
ResultSet rst = stmt.executeQuery("select musician, music_subject, music_year, music_write, music_compose from musictest");
long end = System.currentTimeMillis();
double res1 = (double)(end - start) / 1000;
System.out.println("res1 : "+res1+"초");
long start2 = System.currentTimeMillis();
int j = 1001;
rst.absolute(j);
for(int i = 0 ; i < 100 ; i++){
musician = rst.getString(1);
music_subject = rst.getString(2);
music_year = rst.getString(3);
music_write = rst.getString(4);
music_compose = rst.getString(4);
Vector row = new Vector();
row.add(musician);
row.add(music_subject);
row.add(music_year);
row.add(music_write);
row.add(music_compose);
result.add(row);
rst.next();
}
conn.close();
long end2 = System.currentTimeMillis();
double res2 = (double)(end2 - start2) / 1000;
System.out.println("res2 : "+res2+"초");
}
}catch(Exception e) {
e.printStackTrace();
}finally {
if ( stmt != null ) try{stmt.close();}catch(Exception e){}
if ( conn != null ) try{conn.close();}catch(Exception e){}
}
long end_full = System.currentTimeMillis();
double res_full = (double)(end_full - start_full) / 1000;
System.out.println("res_full : "+res_full+"초");
}
public Vector getResult(){
return result;
}
public static void main(String[] args) {
DBTest5 db = new DBTest5();
db.init();
Vector result = db.getResult();
long start = System.currentTimeMillis();
for(int i=0; i < result.size(); i++){
Vector row = (Vector)result.get(i);
String musician = (String)row.get(0);
String music_subject = (String)row.get(1);
String music_year = (String)row.get(2);
String music_write = (String)row.get(3);
String music_compose = (String)row.get(4);
System.out.println(musician +" : "+ music_subject + " : "+ music_year + " : "+ music_write + " : "+music_compose);
}
long end = System.currentTimeMillis();
double res2 = (double)(end - start) / 1000;
System.out.println("res3 : "+res2+"초");
}
}
=============================================
결과는 (4)에서.. 계속..
***** 아름다운프로님에 의해서 게시물 복사 + 카테고리변경되었습니다 (2003-12-18 17:44)
