Java Tutorial/Database/Batch Update — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
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(нет различий)
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Текущая версия на 05:05, 1 июня 2010
Содержание
Add batch SQL command into Statement
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
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 = getConnection();
conn.setAutoCommit(false);
Statement st = conn .createStatement();
st.executeUpdate("create table survey (id int, name VARCHAR(30) );");
st.addBatch("DELETE FROM survey");
st.addBatch("INSERT INTO survey(id, name) "+
"VALUES(444, "ginger")");
// we intentionally pass a table name (animals_tableZZ)
// that does not exist
st.addBatch("INSERT INTO survey(id, name) "+
"VALUES(555, "lola")");
st.addBatch("INSERT INTO survey(id, name) "+
"VALUES(666, "freddy")");
// Execute the batch
int[] updateCounts = st.executeBatch();
checkUpdateCounts(updateCounts);
// since there were no errors, commit
conn.rumit();
ResultSet rs = st.executeQuery("SELECT * FROM survey");
outputResultSet(rs);
rs.close();
st.close();
conn.close();
}
public static void checkUpdateCounts(int[] updateCounts) {
for (int i=0; i<updateCounts.length; i++) {
if (updateCounts[i] >= 0) {
System.out.println("OK; updateCount="+updateCounts[i]);
}
else if (updateCounts[i] == Statement.SUCCESS_NO_INFO) {
System.out.println("OK; updateCount=Statement.SUCCESS_NO_INFO");
}
else if (updateCounts[i] == Statement.EXECUTE_FAILED) {
System.out.println("Failure; updateCount=Statement.EXECUTE_FAILED");
}
}
}
private static void outputResultSet(ResultSet rs) throws Exception {
ResultSetMetaData rsMetaData = rs.getMetaData();
int numberOfColumns = rsMetaData.getColumnCount();
for (int i = 1; i < numberOfColumns + 1; i++) {
String columnName = rsMetaData.getColumnName(i);
System.out.print(columnName + " ");
}
System.out.println();
System.out.println("----------------------");
while (rs.next()) {
for (int i = 1; i < numberOfColumns + 1; i++) {
System.out.print(rs.getString(i) + " ");
}
System.out.println();
}
}
private static Connection getConnection() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
String url = "jdbc:hsqldb:mem:data/tutorial";
return DriverManager.getConnection(url, "sa", "");
}
}
OK; updateCount=0 OK; updateCount=1 OK; updateCount=1 OK; updateCount=1 ID NAME ---------------------- 444 ginger 555 lola 666 freddy
Check Batch Update count
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
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 = getConnection();
conn.setAutoCommit(false);
Statement st = conn .createStatement();
st.executeUpdate("create table survey (id int, name VARCHAR(30) );");
String INSERT_RECORD = "insert into survey(id, name) values(?,?)";
PreparedStatement pstmt = conn.prepareStatement(INSERT_RECORD);
pstmt.setString(1, "1");
pstmt.setString(2, "name1");
pstmt.addBatch();
pstmt.setString(1, "2");
pstmt.setString(2, "name2");
pstmt.addBatch();
// execute the batch
int[] updateCounts = pstmt.executeBatch();
checkUpdateCounts(updateCounts);
// since there were no errors, commit
conn.rumit();
ResultSet rs = st.executeQuery("SELECT * FROM survey");
outputResultSet(rs);
rs.close();
st.close();
conn.close();
}
public static void checkUpdateCounts(int[] updateCounts) {
for (int i=0; i<updateCounts.length; i++) {
if (updateCounts[i] >= 0) {
System.out.println("OK; updateCount="+updateCounts[i]);
}
else if (updateCounts[i] == Statement.SUCCESS_NO_INFO) {
System.out.println("OK; updateCount=Statement.SUCCESS_NO_INFO");
}
else if (updateCounts[i] == Statement.EXECUTE_FAILED) {
System.out.println("Failure; updateCount=Statement.EXECUTE_FAILED");
}
}
}
private static void outputResultSet(ResultSet rs) throws Exception {
ResultSetMetaData rsMetaData = rs.getMetaData();
int numberOfColumns = rsMetaData.getColumnCount();
for (int i = 1; i < numberOfColumns + 1; i++) {
String columnName = rsMetaData.getColumnName(i);
System.out.print(columnName + " ");
}
System.out.println();
System.out.println("----------------------");
while (rs.next()) {
for (int i = 1; i < numberOfColumns + 1; i++) {
System.out.print(rs.getString(i) + " ");
}
System.out.println();
}
}
private static Connection getConnection() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
String url = "jdbc:hsqldb:mem:data/tutorial";
return DriverManager.getConnection(url, "sa", "");
}
}
OK; updateCount=1 OK; updateCount=1 ID NAME ---------------------- 1 name1 2 name2
Check BatchUpdateException
import java.sql.BatchUpdateException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
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 = getConnection();
conn.setAutoCommit(false);
Statement st = conn.createStatement();
st.executeUpdate("create table survey (id int, name VARCHAR(30) );");
String INSERT_RECORD = "insert into survey(id, name) values(?,?)";
PreparedStatement pstmt = conn.prepareStatement(INSERT_RECORD);
pstmt.setString(1, "1");
pstmt.setString(2, "name1");
pstmt.addBatch();
pstmt.setString(1, "2");
pstmt.setString(2, "name2");
pstmt.addBatch();
try {
// execute the batch
int[] updateCounts = pstmt.executeBatch();
} catch (BatchUpdateException e) {
int[] updateCounts = e.getUpdateCounts();
checkUpdateCounts(updateCounts);
try {
conn.rollback();
} catch (Exception e2) {
e.printStackTrace();
System.exit(1);
}
}
// since there were no errors, commit
conn.rumit();
ResultSet rs = st.executeQuery("SELECT * FROM survey");
outputResultSet(rs);
rs.close();
st.close();
conn.close();
}
public static void checkUpdateCounts(int[] updateCounts) {
for (int i = 0; i < updateCounts.length; i++) {
if (updateCounts[i] >= 0) {
System.out.println("OK; updateCount=" + updateCounts[i]);
} else if (updateCounts[i] == Statement.SUCCESS_NO_INFO) {
System.out.println("OK; updateCount=Statement.SUCCESS_NO_INFO");
} else if (updateCounts[i] == Statement.EXECUTE_FAILED) {
System.out.println("Failure; updateCount=Statement.EXECUTE_FAILED");
}
}
}
private static void outputResultSet(ResultSet rs) throws Exception {
ResultSetMetaData rsMetaData = rs.getMetaData();
int numberOfColumns = rsMetaData.getColumnCount();
for (int i = 1; i < numberOfColumns + 1; i++) {
String columnName = rsMetaData.getColumnName(i);
System.out.print(columnName + " ");
}
System.out.println();
System.out.println("----------------------");
while (rs.next()) {
for (int i = 1; i < numberOfColumns + 1; i++) {
System.out.print(rs.getString(i) + " ");
}
System.out.println();
}
}
private static Connection getConnection() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
String url = "jdbc:hsqldb:mem:data/tutorial";
return DriverManager.getConnection(url, "sa", "");
}
}
ID NAME ---------------------- 1 name1 2 name2
Determining If a Database Supports Scrollable Result Sets
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
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);
DatabaseMetaData dmd = connection.getMetaData();
if (dmd.supportsResultSetType(ResultSet.TYPE_SCROLL_INSENSITIVE)) {
System.out.println("Insensitive scrollable result sets are supported");
}
if (dmd.supportsResultSetType(ResultSet.TYPE_SCROLL_SENSITIVE)) {
System.out.println("Sensitive scrollable result sets are supported");
}
if (!dmd.supportsResultSetType(ResultSet.TYPE_SCROLL_INSENSITIVE)
&& !dmd.supportsResultSetType(ResultSet.TYPE_SCROLL_SENSITIVE)) {
System.out.println("Updatable result sets are not supported");
}
}
}
Use Batch Multiple Updates with PreparedStatement
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
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 = getConnection();
conn.setAutoCommit(false);
Statement st = conn .createStatement();
st.executeUpdate("create table survey (id int, name VARCHAR(30) );");
String INSERT_RECORD = "insert into survey(id, name) values(?,?)";
PreparedStatement pstmt = conn.prepareStatement(INSERT_RECORD);
pstmt.setString(1, "1");
pstmt.setString(2, "name1");
pstmt.addBatch();
pstmt.setString(1, "2");
pstmt.setString(2, "name2");
pstmt.addBatch();
// execute the batch
int[] updateCounts = pstmt.executeBatch();
checkUpdateCounts(updateCounts);
// since there were no errors, commit
conn.rumit();
ResultSet rs = st.executeQuery("SELECT * FROM survey");
outputResultSet(rs);
rs.close();
st.close();
conn.close();
}
public static void checkUpdateCounts(int[] updateCounts) {
for (int i=0; i<updateCounts.length; i++) {
if (updateCounts[i] >= 0) {
System.out.println("OK; updateCount="+updateCounts[i]);
}
else if (updateCounts[i] == Statement.SUCCESS_NO_INFO) {
System.out.println("OK; updateCount=Statement.SUCCESS_NO_INFO");
}
else if (updateCounts[i] == Statement.EXECUTE_FAILED) {
System.out.println("Failure; updateCount=Statement.EXECUTE_FAILED");
}
}
}
private static void outputResultSet(ResultSet rs) throws Exception {
ResultSetMetaData rsMetaData = rs.getMetaData();
int numberOfColumns = rsMetaData.getColumnCount();
for (int i = 1; i < numberOfColumns + 1; i++) {
String columnName = rsMetaData.getColumnName(i);
System.out.print(columnName + " ");
}
System.out.println();
System.out.println("----------------------");
while (rs.next()) {
for (int i = 1; i < numberOfColumns + 1; i++) {
System.out.print(rs.getString(i) + " ");
}
System.out.println();
}
}
private static Connection getConnection() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
String url = "jdbc:hsqldb:mem:data/tutorial";
return DriverManager.getConnection(url, "sa", "");
}
}
OK; updateCount=1 OK; updateCount=1 ID NAME ---------------------- 1 name1 2 name2
Using a Loop to Set Values
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
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 = getConnection();
conn.setAutoCommit(false);
Statement st = conn .createStatement();
st.executeUpdate("create table survey (id int, name VARCHAR(30) );");
String INSERT_RECORD = "insert into survey(id, name) values(?,?)";
PreparedStatement pstmt = conn.prepareStatement(INSERT_RECORD);
for(int i=0;i<10;i++){
pstmt.setInt(1, i);
pstmt.setString(2, "name"+i);
pstmt.executeUpdate();
}
ResultSet rs = st.executeQuery("SELECT * FROM survey");
outputResultSet(rs);
rs.close();
st.close();
conn.close();
}
private static void outputResultSet(ResultSet rs) throws Exception {
ResultSetMetaData rsMetaData = rs.getMetaData();
int numberOfColumns = rsMetaData.getColumnCount();
for (int i = 1; i < numberOfColumns + 1; i++) {
String columnName = rsMetaData.getColumnName(i);
System.out.print(columnName + " ");
}
System.out.println();
System.out.println("----------------------");
while (rs.next()) {
for (int i = 1; i < numberOfColumns + 1; i++) {
System.out.print(rs.getString(i) + " ");
}
System.out.println();
}
}
private static Connection getConnection() throws Exception {
Class.forName("org.hsqldb.jdbcDriver");
String url = "jdbc:hsqldb:mem:data/tutorial";
return DriverManager.getConnection(url, "sa", "");
}
}
ID NAME ---------------------- 0 name0 1 name1 2 name2 3 name3 4 name4 5 name5 6 name6 7 name7 8 name8 9 name9