sql: support CREATE TABLE ... PARTITION BY ... AS ...

[tmercieca]

Tables can have partitioning applied to them, however this functionality was not available through the CREATE TABLE AS syntax. This commit updates the grammar to support PARTITION BY to the CREATE TABLE AS syntax, and the related
functionality.

Fixes: #20178

Release note (sql change): add support for PARTITION BY on CREATE TABLE AS

[blathers-crl]

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[cockroach-teamcity]

This change is 

[tmercieca]

I would like to point out that the syntax adopted in this PR is CREATE TABLE ... PARTITION BY ... AS .... The opt_partition_by_table rule is placed before opt_table_with production rule to be in line with the syntax adopted by create_table_stmt.

[tmercieca]

While working on this PR, I noticed a strange interaction with the testing framework which executes the create_table test cases. When marking a test case which can be parsed successfully (does not output error) with error, the test passes. I am expecting the test to fail as the statement did not error. For example, consider the following test case which can be parsed successfully. Despite labeling it with error and not producing any error, the test passes. Actually, the test passes with both error and parse tags, which seems counterintuitive.

error
CREATE TABLE IF NOT EXISTS a (b) PARTITION BY RANGE (b) (
   PARTITION p1 VALUES FROM (MINVALUE) TO (1),
   PARTITION p2 VALUES FROM (2, MAXVALUE) TO (4, 4),
   PARTITION p3 VALUES FROM (4, 4) TO (MAXVALUE))
AS
SELECT 1
----

Should I open an issue or is this intended?

[blathers-crl]

Thank you for updating your pull request.

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[rafiss]

thanks for your contribution! can you also add a test case for this in pkg/sql/logictest/testdata/logic_test/create_table?

[tmercieca]

@rafiss I have just added test cases in pkg/sql/logictest/testdata/logic_test/create_table as per your suggestion. Due to your input I discovered an additional change needed in pkg/sql/sem/tree/create.go! 👍 ... thank you :)
Apologies for the delay in actioning this change.
Could I kindly request another review?