What is the return type of a “count” query against MySQL using Java JDBC?
The return type of count is long. The Java statement is as follows
rs.next();
long result= rs.getLong("anyAliasName");First, create a table with some records in our sample database test3. The query to create a table is as follows
mysql> create table CountDemo
-> (
-> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> Name varchar(20)
-> );
Query OK, 0 rows affected (0.60 sec)
Insert some records in the table using insert command.
The query is as follows
mysql> insert into CountDemo(Name) values('John');
Query OK, 1 row affected (0.21 sec)
mysql> insert into CountDemo(Name) values('Carol');
Query OK, 1 row affected (0.16 sec)
mysql> insert into CountDemo(Name) values('Bob');
Query OK, 1 row affected (0.19 sec)
mysql> insert into CountDemo(Name) values('David');
Query OK, 1 row affected (0.16 sec)Display all records from the table using select statement.
The query is as follows
mysql> select *from CountDemo;
The following is the output
+----+-------+
| Id | Name |
+----+-------+
| 1 | John |
| 2 | Carol |
| 3 | Bob |
| 4 | David |
+----+-------+
4 rows in set (0.00 sec)
Here is the Java code return type of a “count” query against MySQL using Java JDBC
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class ReturnTypeOfCount {
public static void main(String[] args) {
Connection con=null;
Statement st=null;
ResultSet rs=null;
try {
con=DriverManager.getConnection("jdbc:mysql://localhost:3306/test3?useSSL=false",
"root","123456");
String yourQuery = "SELECT COUNT(*) AS totalCount FROM CountDemo";
st = con.createStatement();
rs = st.executeQuery(yourQuery);
rs.next();
long result= rs.getLong("totalCount");
System.out.println("Total Count="+result);
} catch(Exception e) {
e.printStackTrace();
}
}
}The following is the output
Total Count=4
Here is the snapshot of the output:
Published on 29-Mar-2019 11:17:46
