PostgreSQL allows date and timestamp (with or without time zone) values of infinity and -infinity. These different behaviors accurately reflect how PostgreSQL treats the two types differently. When an OffsetDateTime created in Java is mapped to a PostgreSQL timestamp with time zone, if its offset is not zero, the value adjusted to UTC is used. When a timestamp with time zone is mapped to a, the Java value will always have a zone offset of zero (UTC).
When a time with time zone is mapped to a, the Java value will have a zone offset equal to the one assigned to the value in PostgreSQL, and so in the reverse direction. Mapping of time and timestamp with time zone That is still a distinguishable value (as the PostgreSQL resolution is only to microseconds), so the PostgreSQL 24 value is bidirectionally mapped to that. PostgreSQL accepts 24:00:00.000000 as a valid time, while a day for LocalTime or OffsetTime maxes out at the preceding nanosecond.
#Postgresql current timestamp code
Any code developed for PL/Java and Java 8 or newer is strongly encouraged to use these types for date/time manipulations, for their much better fit to the PostgreSQL types. The java.time types can also be used as parameter and return types of PL/Java functions without special effort (the generated function declarations will make the right conversions happen), and passed to the setter methods of prepared statements, writable result sets (for triggers or composite-returning functions), and SQLOutput for UDTs.Ĭonversions to and from these types never involve the PostgreSQL session time zone, which can vary from session to session.
#Postgresql current timestamp update
Instead, the update takes advantage of the general purpose ResultSet.getObject methods that take a Class parameter (added in JDBC 4.1), and likewise the SQLInput.readObject method with a Class parameter (overlooked in 4.1 but added in 4.2), so a caller can request a java.time class by passing the right Class: Correspondence of PostgreSQL date/time types and Java 8 java.time classes PostgreSQL type The getDate, getTime, and getTimestamp methods on a ResultSet still return the same java.sql types, and so does getObject in the form that does not specify a class. To avoid a breaking change, JDBC 4.2 does not modify what any of the pre-existing JDBC API does by default. These new types are a much better fit to the corresponding PostgreSQL types than the original JDBC java.sql Date/ Time/ Timestamp classes. JDBC 4.2 (the version in Java 8) allows those as alternate Java class mappings of the SQL types date, time (with and without timezone), and timestamp (with/without timezone). Java 8 introduced the much improved set of date/time classes in the java.time package specified by JSR 310. While these particular issues are expected to be fixed in a future PL/Java release, the Java 8 / JDBC 4.2 mappings described next are the strongly-recommended alternative to the legacy mappings, avoiding these issues entirely. There are known issues of long standing in PL/Java’s conversions to and from these types, detailed in issue #200. The conversions of non-zoned values involve a hidden dependency on the PostgreSQL session’s current setting of TimeZone, which can vary from session to session at the connecting client’s preference. For all of these conversions but one, PL/Java must do time zone computations, with the one exception being, unintuitively, timestamp with time zone. Those classes have never been a good representation for PostgreSQL date/time values, because they are based on, which implies knowledge of a time zone, even when they are used to represent PostgreSQL values with no time zone at all. The JDBC getObject and readObject methods that do not take a Class parameter will return objects of those types when retrieving PostgreSQL date or time values. PL/Java function parameters and returns can be declared in Java to have those types, objects of those types can be passed to tObject, ResultSet.updateObject, and SQLOutput.writeObject methods, as well as to the methods that are specific to those types. The first mappings to be specified in JDBC used the JDBC-specific classes, , and, all of which are based on (but only as an implementation detail they should always be treated as their own types and not as instances of ). Mapping between PostgreSQL and Java date/time types Legacy JDBC mappings
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