[Bug]: WEEK(date, mode) two-argument form rejected with 'bad value [DATE BIGINT]'

[dengn]

Branch Name

main (v3.0.9 release tag)

Commit ID

39cfa47

Other Environment Information

• Hardware parameters: n/a (release build)
• OS type: n/a
• Others: discovered via NL2SQL workload generating standard MySQL syntax

Actual Behavior

Calling WEEK(date, mode) with the standard 2-argument form fails at runtime with an "invalid argument" error reporting the type combination [DATE BIGINT] is not accepted.

ERROR 20203 (HY000): invalid argument function week, bad value [DATE BIGINT]

Expected Behavior

MySQL WEEK(date, mode) is a standard 2-argument function where:

• date is a DATE / DATETIME
• mode is an integer 0..7 controlling the week-numbering semantics (whether week starts on Sunday/Monday, whether it's an ISO week, etc.)

It should accept an integer literal (parsed as BIGINT) for the mode argument and either auto-cast to the expected smaller integer type or document/permit the BIGINT path.

Reference: https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html#function_week

Steps to Reproduce

-- 1-arg form works:
SELECT WEEK(CURRENT_DATE);

-- 2-arg form fails with error 20203:
SELECT WEEK(CURRENT_DATE, 3);
SELECT WEEK(CURRENT_DATE, 0);
SELECT WEEK('2026-04-20', 3);

Additional information

The error string bad value [DATE BIGINT] suggests MatrixOne's WEEK only registers a signature for one argument type (or for (DATE, smaller-int)) and the integer literal 3 is being typed as BIGINT without an implicit conversion path.

Suggested fix paths:

1. Register a WEEK(DATE, INT64) signature; or
2. Add an implicit BIGINT → smaller-int cast for mode; or
3. Treat literal integers in this argument position as a constrained type.

This is one of three related issues filed from the same NL2SQL session that produced typical "this week vs last week" SQL. The other two are:

• YEARWEEK function not supported (preferred cleanest form)
• Parser error on arithmetic expression inside INTERVAL clause (fallback path also broken)

The combined effect is that agents (and human users) writing standard MySQL week-aligned comparisons have no working idiom available in v3.0.9.