[SPARK-51562][SQL] Add the time() function

[senthh]

What changes were proposed in this pull request?

This PR adds new function time() which should cast an expr to TIME. This function is a synonym for CAST(expr AS TIME)

Examples

SELECT time('12:25:13.45');
12:25:13.45
SELECT time(timestamp'2020-04-30 12:25:13.45');
12:25:13.45
SELECT time(123);
00:02:03

Why are the changes needed?

This function is a synonym for CAST(expr AS TIME)

Does this PR introduce any user-facing change?

No

How was this patch tested?

By running the related test suites:

$ build/sbt "test:testOnly *ExpressionInfoSuite"
$ build/sbt "test:testOnly *TimeExpressionsSuite"
$ build/sbt "sql/testOnly org.apache.spark.sql.SQLQueryTestSuite -- -z time.sql"

and also with spark-shell

scala> spark.sql("select time(123) as col").show()
+--------+
|     col|
+--------+
|00:02:03|
+--------+


scala> spark.sql("select time(timestamp'2020-04-30 00:25:13.45') as col").show()
+-----------+
|        col|
+-----------+
|00:25:13.45|
+-----------+


scala> spark.sql("select time('12:25:13.45') as col").show()
+-----------+
|        col|
+-----------+
|12:25:13.45|
+-----------+

Was this patch authored or co-authored using generative AI tooling?

No

[senthh]

@MaxGekk Could you please review this PR?

[MaxGekk]

This function is a synonym for CAST(expr AS TIME)

As you wrote in the PR description, the function is just a synonym of CAST. Let's just implement that precisely, and map time() to the Cast expression.

[senthh]

This function is a synonym for CAST(expr AS TIME)

As you wrote in the PR description, the function is just a synonym of CAST. Let's just implement that precisely, and map time() to the Cast expression.

Sure @MaxGekk I will change the implementation such that time will map to cast expression

[senthh]

@MaxGekk Closing this PR as commits got Messed-up, will create new PR