Does JDBC Convert Java Date to Database Session Time Zone for SQL TIMESTAMP?

Does JDBC convert a Java Date object to the database session time zone when writing to an SQL TIMESTAMP column?

When working with JDBC to insert a Java Date into an SQL TIMESTAMP column, it's crucial to understand how time zones are handled. JDBC does not automatically convert the Java Date from the JVM's default time zone to the database session time zone when performing inserts. Instead, it relies on the provided Java Date representation, which is in UTC format. However, the actual behavior might differ based on specific JDBC driver implementations and database configurations.

String insertSQL = "INSERT INTO Events (event_time) VALUES (?)";
PreparedStatement preparedStatement = connection.prepareStatement(insertSQL);
java.util.Date javaDate = new java.util.Date();  // Current date
preparedStatement.setTimestamp(1, new java.sql.Timestamp(javaDate.getTime()));
preparedStatement.executeUpdate();

Causes

• Java Date object is represented in the local time zone of the JVM.
• SQL TIMESTAMP columns are timezone-sensitive and can behave differently based on session settings.

Solutions

• Ensure that your application explicitly formats the Java Date in UTC before sending it to the database.
• Use TimeZone settings within your application or JDBC driver connection properties to align the JVM and database time zones.
• Consider using java.time package (Java 8 and above) which provides better handling of time zones with LocalDateTime and ZonedDateTime.

Mistake: Assuming that the Java Date object automatically converts to the database session's time zone.

Solution: Always convert or format the date to UTC before inserting it into the SQL TIMESTAMP column.

Mistake: Not considering the application server's time zone configuration.

Solution: Ensure the server's time zone matches the expected timezone of the database session.