【发布时间】：2019-03-29 13:53:12
【问题描述】：
我有一个名为 OrderEvent 的父实体和一个名为 PreCondition 的子实体。一个 OrderEvent 可以有多个前提条件（>= 200）。我需要保存 100000 OrderEvent + 100000 * 200 PreCondition。我使用 Repository.save(list Of OrderEvents) 并为每 1000 条记录保存到数据库中。插入 1000 个 OrderEvent 大约需要 30 秒。
保存所有 100000 个 OrderEvent 需要将近一个小时。
有没有办法把时间降到 2 分钟以下？
尝试了存储库的保存实体方法
public void parseOrder(String path, String collectionName) throws ParseException {
BufferedReader reader;
Connection conn = (Connection) em.unwrap(java.sql.Connection.class);
System.out.println(conn);
try {
reader = new BufferedReader(new FileReader(
path));
String line = reader.readLine();
String jobNumber = line.substring(0, 7).trim();
String recordType = line.substring(7, 9).trim();
Integer len = line.length();
preId = 0L;
postId = 0L;
eventId = 0L;
OrderEvent orderEvent = this.paraseHeader(line,len,jobNumber,collectionName);
Integer count = 1;
Integer batch = 0;
long startTime = System.nanoTime();
List<OrderEvent> list = new ArrayList<OrderEvent>();
while (line != null) {
line = reader.readLine();
if (line == null) {
continue;
}
jobNumber = line.substring(0, 7).trim();
recordType = line.substring(7, 9).trim();
len = line.length();
if (recordType.equals("0H")) {
count++;
batch++;
if (batch.equals(1000)) {
orderRepository.save(list);
list.clear();
long estimatedTime = System.nanoTime() - startTime;
System.out.println("Processed " + batch + " records in " + estimatedTime / 1_000_000_000. + " second(s).");
batch = 0;
startTime = System.nanoTime();
}
list.add(orderEvent);
//orderRepository.saveAndFlush(orderEvent);
orderEvent = this.paraseHeader(line,len,jobNumber,collectionName);
} else if (recordType.equals("2F")) {
this.paraseFeature(line,len,jobNumber,orderEvent);
}
}
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
private OrderEvent paraseHeader (String line,Integer len,String jobNumber,String collectionName) throws ParseException {
String model = line.substring(9, 16).trim();
String processDate = line.substring(len-11,len-3).trim();
String formattedProcessDate = processDate.substring(0,4) + "-" +
processDate.substring(4,6) +"-" + processDate.substring(6,8) + " 00:00:00";
//eventId++;
OrderEvent orderEvent = new OrderEvent(jobNumber,UUID.randomUUID().toString(),collectionName,
formatter.parse(formattedProcessDate));
// preId++;
//postId++;
orderEvent.fillPrecondition("Model", "Stimulus", "OP_EQ", model);
orderEvent.fillPostcondition("Add_Fact","Coded","Response","True");
return orderEvent;
}
private void paraseFeature (String line,Integer len, String jobNumber, OrderEvent orderEvent) {
// preId++;
String feature = line.substring(len-7,len).trim();
orderEvent.fillPrecondition("Feature", "Stimulus", "OP_EQ", feature);
}
【问题讨论】：
-
如果你确定你没有违反任何约束，你可以禁用约束然后插入行然后重新激活约束。
-
顺便说一句，您没有保存可能少于 1000 个的“剩余”批次。（除非您始终只需要准确处理
n x 1000订单...）