JDBC (Java Database Connectivity) provides a standard API for connecting to and interacting with relational databases. The key aspects are: 1) JDBC standardizes the connection establishment and query execution process but not the actual SQL syntax. 2) There are three main types of statements - regular statements, prepared statements, and callable statements - that allow executing SQL queries and commands. 3) The basic steps to use JDBC are: load the driver, define the connection URL, establish a connection, create a statement, execute queries, process results, and close the connection. 4) Transactions allow grouping statements together to commit or rollback as a single unit of work.

1. JDBC

2. Definition
• JDBC – Java Database Connectivity
• JDBC provides standard library for accessing relational database
• API standardize: connection establishment, query initiation, method
to stored query, data structure of query syntax
• API doesn’t standardize SQL syntax
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3. JDBC Datatypes
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4. 7 Steps Using JDBC
Load the
driver
Define the
Connection
URL
Establish
The
Connection
Create a
Statement
Object
Execute a
Query
Process
Results
Close the
Connection
1 2 3 4 5
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6 7

5. Step 1 – Load the Driver
try {
Class.forName("org.postgresql.Driver");
Class.forName("com.mysql.jdbc.Driver");
}
catch (ClassNotFoundException e) {
System.out.println("Error Loading Driver :
"+e);
}
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6. Step 2 – Define the Connection
URL
String host = "dbserver.bandung.go.id";
String db = "db_simpeg";
int port = 3036;
String mysqlURL = “jdbc:mysql//”+ host +“:”+ port
+“/”+ db;
String oracleURL = “jdbc:oracle:thin:@”+ host +“:”+
port +“:”+ db;
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7. Step 3 – Establish the
Connection
String username = “dbUserLogin”;
String password = “dbUserPassword”;
Connection connection =
DriverManager.getConnection(mysqlURL, username,
password);
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8. Step 4 – Create Statement
Statement statement = connection.createStatement();
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9. Step 5 – Execute a Query
String query = “SELECT column1, column2, column3 FROM table”;
ResultSet rs = statement.executeQuery(query);
• Use statement.executeUpdate if you want to modify the database.
These modifying operations includes INSERT, UPDATE and
DELETE.
String query = “INSERT INTO table VALUES (value1, value2,
value3)”;
ResultSet rs = statement.executeUpdate(query);
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10. Step 6 – Process the Result
String nama = “”;
String alamat = “”;
float nilai = 0.0;
int noUrut = 0;
while (rs.next()) {
nama = rs.getString(1); // the 1st column number is 1 not 0.
alamat = rs.getString(2);
nilai = rs.getFloat(3);
noUrut = rs.getInt(4);
}
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11. Step 7 – Close the Connection
connection.close();
• Use this statement only if you are sure that there is
no more database operation will be proceed.
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12. Statement
• SQL statements are sent to the database through
Statement object.
• Three types of statement objects :
• Statement - for executing a simple SQL statement
• Prepared Statement - for executing a pre-compiled
SQL statement that use parameters
• Callable Statement - for executing a database stored
procedure
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13. Prepared Statement
• Execute the same SQL statement multiple times.
• Create statement in standard form that is sent to the database
for compilation before actually being used
• Mark the parameters using "?" and replace it using setXXX
methods when ready to manipulate them
• Prepared Statement execute these parameters without
arguments.
• execute
• executeQuery()
• executeUpdate()
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14. Prepared Statement Example
Connection connection = DriverManager.getConnection(url, user, password);
PreparedStatement statement =
connection.prepareStatement("UPDATE accounts "+
"SET debit = ?, credit = ? WHERE id = ?");
int[] debits = getDebits();
int[] credits = getCredits();
int[] ids = getIds();
for(int i=0; i<credits.length; i++) {
statement.setInt(1, debits[i]);
statement.setInt(2, credits[i]);
statement.setInt(3, ids[i]);
statement.executeUpdate();
}
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15. Transaction
• Every time we execute an SQL statement, it is
automatically committed to database by default.
• Turn auto commit off to group two or more
statements together into a transaction
• connection.setAutoCommit(false);
• Call commit to permanently record the changes to
database after executing a group of statements
• Call rollback if an error occurs
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16. Transaction Example
Connection connection = DriverManager.getConnection(url, username, passwd);
connection.setAutoCommit(false);
try {
statement.executeUpdate(...);
statement.executeUpdate(...);
} catch(SQLException e) {
try {
connection.rollback();
} catch(SQLException e) { }
} finally {
try {
connection.commit();
connection.close();
} catch(SQLException e) {}
}
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17. Tugas
Buat sebuah program, menggunakan Java Swing, connect ke database
(boleh MySQL, boleh PostgreSQL), setidaknya memiliki fitur CRUD
- Create a single record
- Retrieve data from table
- Update a single record
- Delete a single record
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18. Thank you
Bayu Rimba Pratama, ST, M.Kom