How to collect from a "timestamp without time zone" Field to a Java Timestamp without Timezone

Question

My Jooq Query:

dslContext.select(
                timeInterval,
                ifnull(avg(field(FieldName.AVERAGE, Double.class))
                        .cast(Double.class), 0.0))
                .from(channelTimebucketQuery)
                .groupBy(timeInterval)
                .orderBy(timeInterval)
                .collect(Collectors.toMap(Record2::component1, Record2::component2));

returns a Timestamp with a Timezone attached to it and a double

But my Profiler says it should return a Timestamp without timezone.

select pg_typeof(time_bucket) from (

    select "alias_67258973"."time_bucket", coalesce(cast(avg(average) as double precision), 0.0) from (select "public"."time_bucket_gapfill"("bucket_width" := cast("public"."create_interval"("seconds" := 43200) as "pg_catalog"."interval"), "ts" := cast("public"."testTable"."time" as timestamp), "start" := cast(null as timestamp), "finish" := cast(null as timestamp)) as "time_bucket", avg("public"."testTable"."average") as "average" from "testTable" where ("public"."testTable"."device" in ('702088'  ) and "public"."testTable"."time" >= timestamp '2020-02-10 13:57:28.2212375' and "public"."testTable"."time" <= timestamp '2020-02-24 13:57:28.2222399') group by time_bucket) as "alias_67258973" group by "alias_67258973"."time_bucket" order by "alias_67258973"."time_bucket"
        ) as x;

Where does the Timezone come from? How do i get the timezone to + 0000

Answer 1

The default JDBC type for the SQL type TIMESTAMP WITHOUT TIME ZONE (or just TIMESTAMP ) is java.sql.Timestamp . For historical reasons, which we all regret, java.sql.Timestamp extends java.util.Date , which models a TIMESTAMP WITHOUT TIME ZONE by associating your JVM time zone (ie TimeZone.getDefault() ) with a unix timestamp.

A much better representation of the SQL TIMESTAMP WITHOUT TIME ZONE data type is java.time.LocalDateTime , which jOOQ supports as well. More recent versions of jOOQ's code generator will have set <javaTimeTypes>true</javaTimeTypes> to make the JSR-310 types the default.

Nevertheless, despite the confusion from the debugger and the associated implicit time zone in java.sql.Timestamp , the two data types are equivalent to one another, and can be transformed to one another via:

• Timestamp.valueOf(LocalDateTime)
• Timestamp.toLocalDateTime()