问题描述
在将其标记为重复之前,请先阅读.我从Google和SO搜索了很多内容,但是我找不到我想要的确切答案.
Please read before marking this as duplicate. I have searched a lot from google and SO, but I couldn't the precise answer I am looking for.
我的问题:在JDBC中,我可以使用单个Statement
对象多次调用executeQuery("")
吗?安全吗?或者应该在每次查询后关闭语句对象,并创建新对象以执行另一个查询.
My Question: In JDBC, Can I use single Statement
object to call executeQuery("")
multiple times? Is it safe? OR should I close the statement object after each query, and create new object for executing another query.
E.G:
Connection con;
Statement s;
ResultSet rs;
ResultSet rs2;
try
{
con = getConnection();
s = con.prepareStatement();
try
{
rs = s.executeQuery(".......................");
// process the result set rs
}
finally
{
close(rs);
}
// I know what to do to rs here
// But I am asking, should I close the Statement s here? Or can I use it again for the next query?
try
{
rs2 = s.executeQuery(".......................");
// process the result set rs2
}
finally
{
close(rs2);
}
}
finally
{
close(s);
close(con);
}
推荐答案
是的,您可以重新使用Statement
(特别是PreparedStatement
),并且通常应在JDBC中使用.这将是效率低下的&如果您不重用您的语句并立即创建另一个相同的Statement
对象,则为错误的样式.至于关闭它,就像在此代码段中一样,将其最终关闭是合适的.
Yes you can re-use a Statement
(specifically a PreparedStatement
) and should do so in general with JDBC. It would be inefficient & bad style if you didn't re-use your statement and immediately created another identical Statement
object. As far as closing it, it would be appropriate to close it in a finally block, just as you are in this snippet.
有关您要查询的内容的示例,请查看以下链接: jOOq文档
For an example of what you're asking check out this link: jOOq Docs
这篇关于使用单个JDBC语句对象执行多个查询的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!