Handling Database Exceptions
Database operations can fail for several reasons: a table may not exist, a column name may be misspelled, or the connection may drop. JDBC uses SQLException to capture these errors, providing details like error messages and SQL state codes.
The query in this exercise has an intentional typo (boks instead of books).
To ćwiczenie jest częścią kursu
Querying a PostgreSQL Database in Java
Instrukcje do ćwiczenia
- Catch the exception when the query fails.
- Print the error message and SQLState from the exception.
Interaktywne ćwiczenie praktyczne
Spróbuj tego ćwiczenia, uzupełniając ten przykładowy kod.
public class Main {
public static void main(String[] args) {
try (Connection conn = DriverManager.getConnection(Credentials.URL, Credentials.USER, Credentials.PASSWORD);
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT * FROM boks")) {
while (rs.next()) {
System.out.println(rs.getString("title"));
System.out.println(rs.getInt("publication_year"));
}
// Catch database exceptions
} catch (____ e) {
// Print the error message and SQLState
System.out.println("Error: " + e.____());
System.out.println("SQLState: " + e.____());
}
}
}