将抓取大小设置为负数

问题描述

我正在使用别人的代码，其中包含以下行:

I'm working with someone else's code, which contains the lines:

Connection conn = dataSource.getConnection();
conn.setAutoCommit(false);

Statement stmt = conn.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY);
stmt.setFetchSize(Integer.MIN_VALUE);

ResultSet rs = stmt.executeQuery(myQuery);

我想知道是否有人可以解释将获取大小设置为Integer.MIN_VALUE的效果?也就是说，它会获取可能存储的最大行数，还是会表现其他方式?

I was wondering if someone could explain the effect of setting the fetch size to Integer.MIN_VALUE? That is, does it fetch the maximum number of rows possible to memory, or does it behave otherwise?

我应该提到我们的数据源是一个C3P0连接池，它使用MySQL JDBC驱动程序.

I should mention that our data source is a C3P0 connection pool, which uses the MySQL JDBC driver.

推荐答案

来自文档(在示例代码段中明确显示了两个createStatement/setFetchSize行):

From the docs (which explicitly show the two createStatement/setFetchSize lines in an example code snippet):

本着钓鱼的精神，我的Google搜索是"mysql fetch size jdbc".

In the spirit of teaching to fish, my google search was "mysql fetch size jdbc".

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