【IT168 技术文章】
以下方法经测试，在环境IBM x346,3.2G×2,4G,RAID 1,DB2 V8.2.4,Win2000 Adv Server，DMS表空间中，数据的load速度在60-100万条/min左右。
背景：需要更改数据库表空间，或者需要将数据库中所有表的数据迁移到一个新的数据库中。
步骤：
1. 通过db2控制台(db2cc)选中源数据库中的所有表，将其导出成DDL脚本;
2. 根据需要对脚本进行必要的修改，譬如更改表空间为GATHER;
3. 新建数据库，新建DMS表空间:GATHER;
4. 将DDL脚本在此数据库中执行;
5. 编写代码查询源数据库中的所有表，自动生成export脚本;
6. 编写代码查询源数据库中的所有表，自动生成import脚本;
7. 连接源数据库执行export脚本;
8. 连接目标数据库执行import脚本;
附录1:生成export脚本代码示例:/**
* 创建导出脚本
* @param conn
* @param creator 表创建者
* @param filePath
*/
public void createExportFile(Connection conn,String creator,String filePath) throws Exception {
DBBase dbBase = new DBBase(conn);
String selectTableSql = "select name from sysibm.systables where creator = '" + creator + "' and type='T'";
try {
dbBase.executeQuery(selectTableSql);
} catch (Exception ex) {
throw ex;
} finally {
dbBase.close();
}
DBResult result = dbBase.getSelectDBResult();
List list = new ArrayList();
while (result.next()) {
String table = result.getString(1);
list.add(table);
}
StringBuffer sb = new StringBuffer();
String enterFlag = "\r\n";
for (int i = 0; i < list.size();i++) {
String tableName = (String)list.get(i);
sb.append("db2 \"export to aa" + String.valueOf(i+1)+ ".ixf of ixf select * from " + tableName + "\"");
sb.append(enterFlag);
}
String str = sb.toString();
FileUtility.saveStringToFile(filePath, str, false);
}
附录2:生成import脚本代码示例:/**
* 创建装载脚本
* @param conn
* @param creator 表创建者
* @param filePath
*/
public void createLoadFile(Connection conn,String creator,String filePath) throws Exception {
DBBase dbBase = new DBBase(conn);
String selectTableSql = "select name from sysibm.systables where creator = '" + creator + "' and type='T'";
try {
dbBase.executeQuery(selectTableSql);
} catch (Exception ex) {
throw ex;
} finally {
dbBase.close();
}
DBResult result = dbBase.getSelectDBResult();
List list = new ArrayList();
while (result.next()) {
String table = result.getString(1);
list.add(table);
}
StringBuffer sb = new StringBuffer();
String enterFlag = "\r\n";
for (int i = 0; i < list.size();i++) {
String tableName = (String)list.get(i);
sb.append("db2 \"load from aa" + String.valueOf(i+1)+ ".ixf of ixf into " + tableName + " COPY NO without prompting \"");
sb.append(enterFlag);
}
String str = sb.toString();
FileUtility.saveStringToFile(filePath, str, false);
}
附录3:export脚本示例db2 connect to testdb user test password test
db2 "export to aa1.ixf of ixf select * from table1"
db2 "export to aa2.ixf of ixf select * from table2"
db2 connect reset
附录4:import脚本示例db2 connect to testdb user test password test
db2 "load from aa1.ixf of ixf replace into table1 COPY NO without prompting "
db2 "load from aa2.ixf of ixf replace into table2 COPY NO without prompting "
db2 connect reset
