pierwsze przykłady JDBC

PC21-BazyDanych/pom.xml

@@ -11,4 +11,12 @@
         <maven.compiler.target>21</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
+    
+    <dependencies>
+        <dependency>
+            <groupId>org.postgresql</groupId>
+            <artifactId>postgresql</artifactId>
+            <version>42.7.5</version>
+        </dependency>
+    </dependencies>
 </project>

PC21-BazyDanych/src/main/java/zajecia/OdczytajEmployees.java

+package zajecia;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+public class OdczytajEmployees {
+
+    public static void main(String[] args) {
+        String url = "jdbc:postgresql://localhost:5432/hr";
+        try(Connection c = DriverManager.getConnection(url, "alx", "abc123")) {
+            System.out.println("mam połączenie: " + c);
+            
+            try(PreparedStatement stmt = c.prepareStatement("SELECT * FROM employees ORDER BY employee_id");
+                ResultSet rs = stmt.executeQuery()) {
+                System.out.println("mam ResultSet: " + rs);
+                
+                while(rs.next()) {
+                    System.out.printf("%s %s (%s), pensja %s\n",
+                            rs.getString("first_name"), rs.getString("last_name"),
+                            rs.getString("job_id"), rs.getBigDecimal("salary"));
+                }
+            }
+        } catch (SQLException e) {
+            e.printStackTrace();
+        };
+
+    }
+
+}
+

PC21-BazyDanych/src/main/java/zajecia/OdczytajOsoby.java

+package zajecia;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+public class OdczytajOsoby {
+
+    public static void main(String[] args) {
+        String url = "jdbc:postgresql://localhost:5432/test";
+        try(Connection c = DriverManager.getConnection(url, "alx", "abc123")) {
+            System.out.println("mam połączenie: " + c);
+            
+            try(PreparedStatement stmt = c.prepareStatement("SELECT * FROM osoby");
+                ResultSet rs = stmt.executeQuery()) {
+                System.out.println("mam ResultSet: " + rs);
+                
+                while(rs.next()) {
+                    System.out.printf("%s %s, ur. %s, pensja %s\n",
+                            rs.getString("imie"), rs.getString("nazwisko"),
+                            rs.getDate("data_ur"), rs.getBigDecimal("zarobki"));
+                }
+            }
+        } catch (SQLException e) {
+            e.printStackTrace();
+        };
+
+    }
+
+}
+