Working with MySQL Datetimes and Timestamps in Java

The interaction between Java applications and a MySQL database often involves manipulating date and time information. Determining the best approach to extracting and inserting date data using a combination of datetimes and timestamps in a Java application is crucial.

Java Date Representation

In Java, the java.util.Date class represents date and time information. It encompasses both date and time components, with precision measured in milliseconds.

MySQL Date and Time Types

MySQL offers three primary date and time data types:

• DATE: Represents only the date portion (year, month, day).
• TIME: Represents only the time portion (hours, minutes, seconds).
• TIMESTAMP: Represents both the date and time components, similar to Java's Date class.

JDBC Representations

In JDBC (Java Database Connectivity), these MySQL types are represented as:

• java.sql.Date for DATE
• java.sql.Time for TIME
• java.sql.Timestamp for TIMESTAMP

Storing Timestamps in MySQL

To store a timestamp in MySQL, use the PreparedStatement#setTimestamp() method.

java.util.Date date = getItSomehow();
Timestamp timestamp = new Timestamp(date.getTime());
preparedStatement = connection.prepareStatement("SELECT * FROM tbl WHERE ts > ?");
preparedStatement.setTimestamp(1, timestamp);

Retrieving Timestamps from MySQL

To retrieve a timestamp from MySQL, use the ResultSet#getTimestamp() method.

Timestamp timestamp = resultSet.getTimestamp("ts");
java.util.Date date = timestamp; // Upcast to java.util.Date

By understanding the differences between Java's Date class and MySQL's date and time types, and using the appropriate JDBC methods, you can effectively manage date information between your Java application and MySQL database.