如何从mysql数据库的arraylist中添加超过50,000,000条记录 [英] How to add more than 50,000,000 records in arraylist from mysql database

问题描述

从数据库中将超过50,000,000条记录添加到数组列表中.我要添加30,000,000条记录，显示堆内存不足错误.

Add into array list more than 50,000,000 records from data base. I am adding 30,000,000 records it showing out of heap memory error .

推荐答案

在这里看看:增加Java中的堆大小

您可以在JVM上设置标志以增加堆大小.使用任何您想使用的东西，但请确保您显然有RAM.

You can set a flag on the JVM to increase the heap size. Use whatever you want but be sure you have the RAM obviously.

从命令行:

java -Xmx8g myprogram
java -Xmx16g myprogram

或者，如果您知道程序需要多少空间，请设置初始堆大小:

Or if you know how much space your program needs, set the initial heap size:

java -Xms4g myprogram

请谨慎使用.正如其他人所评论的那样，这比Java堆的默认限制更可能是您的方法出现的问题.

Use these cautiously. As others have commented, this is more likely a problem with your approach than the default limit of the Java heap.

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