Whenever you want to delete a record from any HSQLDB table, you can use the DELETE FROM command.
Syntax
Here is the generic syntax for the DELETE command to delete data from an HSQLDB table.
DELETE FROM table_name [WHERE Clause]
- If WHERE clause is not specified, then all the records will be deleted from the given MySQL table.
- You can specify any condition using WHERE clause.
- You can delete records in a single table at a time.
Example
Let us consider an example that deletes the record data from the table named tutorials_tbl having id 105. Following is the query that implements the given example.
DELETE FROM tutorials_tbl WHERE id = 105;
After execution of the above query, you will receive the following output −
(1) rows effected
HSQLDB – JDBC Program
Here is the JDBC program that implements the given example. Save the following program into DeleteQuery.java.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
public class DeleteQuery {
public static void main(String[] args) {
Connection con = null;
Statement stmt = null;
int result = 0;
try {
Class.forName("org.hsqldb.jdbc.JDBCDriver");
con = DriverManager.getConnection(
"jdbc:hsqldb:hsql://localhost/testdb", "SA", "");
stmt = con.createStatement();
result = stmt.executeUpdate(
"DELETE FROM tutorials_tbl WHERE id=105");
} catch (Exception e) {
e.printStackTrace(System.out);
}
System.out.println(result+" Rows effected");
}
}
You can start the database using the following command.
\>cd C:\hsqldb-2.3.4\hsqldb
hsqldb>java -classpath lib/hsqldb.jar org.hsqldb.server.Server --database.0
file:hsqldb/demodb --dbname.0 testdb
Compile and execute the above program using the following command.
\>javac DeleteQuery.java
\>java DeleteQuery
After execution of the above command, you will receive the following output −
1 Rows effected
