How get the number of rows count by ResultSet in Java [duplicate]

问题

This question already has answers here:

How do I get the row count in JDBC? (7 answers)

Closed 5 years ago.

I want to get the row count of a ResultSet.

ResultSet rs;
Statement s;
rs=s.executeQuery("SELECT * FROM mytable");

//rs.getRowCount; ???

回答1:

You can go to the last row of the resultset and get the row number like this:

resultSet.last()
int count = resultSet.getRow()

But this is inefficient because it has to read all the table data. Better to execute the query:

SELECT COUNT(*) FROM mytable

回答2:

I think we can get count as given below:

int size = 0;
try {
    while(rs.next()){
        size++;
    }
}
catch(Exception ex) { }

or we can use

ResultSet.getRow()

来源：https://stackoverflow.com/questions/25351452/how-get-the-number-of-rows-count-by-resultset-in-java