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1、批处理的使用：同时执行多个sql语句。可以用事务进行管理。用法参考代码：
[/code]import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
public class BatchDemo {
public static void main(String[] args) {
final String driver="com.mysql.jdbc.Driver";
try {
Class.forName(driver);
Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/sh","sh","123456");
Statement stmt=conn.createStatement();
//关闭自动提交 默认自动提交事务，后续代码使用手动添加事务进行处理
conn.setAutoCommit(false);
//把以下三个insert语句作为一个批处理
stmt.addBatch("insert into employee values(161,'李',27,15000,'欧洲',101,105)");
stmt.addBatch("insert into employee values(162,'李',27,15000,'欧洲',101,105)");
stmt.addBatch("insert into employee values(163,'李',27,15000,'欧洲',101,105)");
//执行批处理，接收每条语句的执行结果 result数组中会存在一组0和1
int[] result=stmt.executeBatch();
for(int i:result){
System.out.println(i);
}
//提交事务
conn.commit();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}
}[/code]2、元数据 MetaData：描述数据库中的一些数据。
1）DataBase MetaData：数据库的元数据。用法参考代码：
[/code]import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
public class MetadataDemo {
public static void main(String[] args) {
final String driver="com.mysql.jdbc.Driver";
try {
Class.forName(driver);
Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/sh","sh","123456");
//数据的元数据：存放数据库的信息或者DBMS的信息
DatabaseMetaData dameta=conn.getMetaData();
System.out.println("驱动的名字"+dameta.getDriverName());
System.out.println("驱动的主版本"+dameta.getDatabaseMajorVersion());
System.out.println("驱动的小版本"+dameta.getDatabaseMinorVersion());
ResultSet rs=dameta.getTables(null, null, "employee", new String[] {"TABLE"});
//rs 结果集里每一列代表返回表中不同的信息
while(rs.next()){
System.out.println(rs.getString(1));
System.out.println(rs.getString(2));
System.out.println(rs.getString(3));//返回表名
System.out.println(rs.getString(4));
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}
}[/code]其中getTables返回的列包含以下数据：
TABLE_CAT String => table catalog (may be null)
TABLE_SCHEM String => table schema (may be null)
TABLE_NAME String => table name
TABLE_TYPE String => table type. Typical types are "TABLE", "VIEW", "SYSTEM TABLE", "GLOBAL TEMPORARY", "LOCAL TEMPORARY", "ALIAS", "SYNONYM".
REMARKS String => explanatory comment on the table
TYPE_CAT String => the types catalog (may be null)
TYPE_SCHEM String => the types schema (may be null)
TYPE_NAME String => type name (may be null)
SELF_REFERENCING_COL_NAME String => name of the designated "identifier" column of a typed table (may be null)
REF_GENERATION String => specifies how values in SELF_REFERENCING_COL_NAME are created. Values are "SYSTEM", "USER", "DERIVED". (may be null)
2）ResultSet MetaData：结果集的元数据。用法参考代码：
[/code]import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
public class MetadataDemo {
public static void main(String[] args) {
final String driver="com.mysql.jdbc.Driver";
try {
Class.forName(driver);
Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/sh","sh","123456");
//结果集的元数据
Statement stmt=conn.createStatement();
ResultSet rs1=stmt.executeQuery("select * from employee");
//获取结果集的元数据
ResultSetMetaData rsMeta=rs1.getMetaData();
System.out.println(rsMeta.getColumnCount());//返回结果集列数
System.out.println(rsMeta.getColumnName(3));//返回结果集第三列的列名
System.out.println(rsMeta.getTableName(2));//返回结果集第2列的表名
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
[/code]————————————————
原文链接：https://blog.csdn.net/heart_1014/article/details/52202943
程序猿的技术大观园：www.javathinker.net
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Java技术网站 → 『 Java开发技术 』 → 『 Java编程技术专题 』 → JDBC API中批处理SQL语句以及获得元数据信息
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