PreparedStatement use, null check

Question

I'm using PreparedStatements in a number of queries that probably don't benefit from it and wondering if the problems I'm having are worth the extra I/O efficiency and security benefits. Thoughts?
Additionally, I'm having trouble knowing for sure if my resultsets from a PS are empty. Here's some sample code:
string sql = "SELECT * FROM atable WHERE id = ?";
PreparedStatement ps = c.prepareStatement(sql);
ps.setString(1, ID);
ResultSet rs = ps.executeQuery();
if(rs == null)
rs.next();
x = rs.getString("acolumn");
I know rs.next() executes because of some debug statements I've worked into the real code, but at getString("acolumn") I get "Exhausted Resultset." When I run the query by hand, it's an empty result. So what should I be using to check for null or 0 row count?

Answer 1

I'm using PreparedStatements in a number of queries
that probably don't benefit from it and wondering if
the problems I'm having are worth the extra I/O
efficiency and security benefits. Thoughts?
Additionally, I'm having trouble knowing for sure if
my resultsets from a PS are empty. Here's some
sample code:
string sql = "SELECT * FROM atable WHERE id = ?";
PreparedStatement ps = c.prepareStatement(sql);
ps.setString(1, ID);
ResultSet rs = ps.executeQuery();
if(rs == null)
rs.next();
x = rs.getString("acolumn");
I know rs.next() executes because of some debug
statements I've worked into the real code, but at
getString("acolumn") I get "Exhausted Resultset."
When I run the query by hand, it's an empty result.
. So what should I be using to check for null or 0
row count?Hi,
Your code should read:
ResultSet rs = ps.executeQuery();
if (rs.next()) {
    // do whatever
}next returns a boolean that says if there was a next or not.
/Kaj