SNOW-1723202: Support Java 8 java.time types

[DenWav]

Java 8 time types are more modern and should be preferred over the old types Date, Time, etc.

• java.time.LocalDate
• java.time.LocalTime
• java.time.LocalDateTime
• java.time.OffsetDateTime
• java.time.ZonedDateTime
• java.time.Instant

The Snowflake documentation specifies:

Although Snowflake can store time values with nanosecond precision, the java.sql.time library maintains only millisecond precision. Conversion between Snowflake and Java data types can reduce effective precision to milliseconds.

This limitation is not present in the modern java.time types, and time zone information is explicit, rather than implicit and prone to error.

Note that proper implementation of this would not involve converting from the old Java types to the new ones, since that would not fix the issue described here.

[sfc-gh-dszmolka]

hi - i'm wondering this could be a little bit of duplicate of snowflakedb/snowflake-jdbc#1494 for the underlying Snowflake JDBC driver ?
Can you please check ?

[DenWav]

Related, and yes indeed we need that ticket for sure. I had to write a really ugly wrapper around the Snowflake JDBC driver to get around that limitation.

But no this is no a duplicate - consider the Row class, for example. There is no way to retrieve Java 8 time types from any columns. getAs(<index|name>, type) presents an API that might look like it does what we need, allowing something like:

getAs(1, LocalDateTime.class)

but that is not true. getAs only delegates to the other get methods. The API here needs to be expanded to support these types, whether or not that depends on the JDBC driver as well is an implementation issue.