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From: Cecil Westerhof <Cecil@decebal.nl>
Newsgroups: comp.lang.java.programmer
Subject: Re: Which databases are the most used with Java
Date: Sun, 13 Aug 2017 23:18:51 +0200
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Arne Vajhøj <arne@vajhoej.dk> writes:

>> What is wrong about that? A Statement can only have one ResultSet. So
>> if you have 10 (independent) ResultSets you have 10 Statements.
>
> No.
>
> A Statement can only have one ResultSet at a given time, but a Statement
> can have multiple ResultSet's over time.
>
> Statement stmt = con.createStatement();
> ResultSet rs1 = stmt.executeQuery("...");
> ...
> rs1.close();
> ResultSet rs2 = stmt.executeQuery("...");
> ...
> rs2.close();
> stmt.close();
>
> is a common construct.
>
> (in newer code it would be one try Statement with two try ResultSet inside)
>
> There are also the possibility in some databases to execute multiple
> SELECT in a single execute/executeQuery and then you will get more than
> one ResultSet back.
>
> This is used like:
>
> Statement stmt = con.createStatement();
> ResultSet rs1 = stmt.executeQuery("...");
> ...
> rs1.close();
> stmt.getMoreResults();
> ResultSet rs2 = stmt.getResultSet();
> ...
> rs2.close();
> stmt.close();

Since Java7 we (or at least I) do not program that way anymore. You
use try with resources. You only want the ResultSet, but to prevent a
resource leak, you need to also create the Statement. That makes my
hair stand up on the back of my neck.

-- 
Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof