Insert type params are not be nullable if the column is nullable

[Nydauron]

In the insertion test cases, the parameter types always evaluate without a null union even if the column is nullable. The expected behavior is that parameters that are representing nullable columns should have the type T | null.

Reproducible Example

An example of this can be found within the test cases:

sqlx-ts/tests/mysql_insert_query_parameters.rs

Lines 41 to 57 in f273e38

	run_test!(should_pick_query_params_from_multiple_rows_of_values, TestConfig::new("mysql", true, None, None),
	//// TS query ////
	r#"
	import { sql } from "sqlx-ts";
	const someInputQuery = sql`
	INSERT INTO items (id, name, rarity, flavor_text)
	VALUES
	(?, ?, 'epic', 'test'),
	(1, 'test', ?, ?);
	`
	"#,
	//// Generated TS interfaces ////
	r#"
	export type SomeInputQueryParams = [[number, string], [string, string]];

The schema of the table items is as follows:

mysql> describe items;
+--------------+--------------+------+-----+---------+----------------+
| Field        | Type         | Null | Key | Default | Extra          |
+--------------+--------------+------+-----+---------+----------------+
| id           | int          | NO   | PRI | NULL    | auto_increment |
| name         | varchar(100) | NO   |     | NULL    |                |
| rarity       | varchar(50)  | YES  |     | NULL    |                |
| inventory_id | int          | YES  | MUL | NULL    |                |
| flavor_text  | text         | YES  |     | NULL    |                |
+--------------+--------------+------+-----+---------+----------------+
5 rows in set (0.00 sec)

The parameter type generated for this query is [[number, string], [string, string]]. It should instead be [[number, string], [string | null, string | null]] since rarity and flavor_text are nullable columns.

Running an insert query manually with rarity and flavor_text set to NULL runs without errors and is present within the table upon read:

mysql> INSERT INTO items (id, name, rarity, flavor_text) VALUES (2, 'awesome', 'epic', 'test'), (1, 'test', NULL, NULL);
Query OK, 2 rows affected (0.01 sec)
Records: 2  Duplicates: 0  Warnings: 0

mysql> select * from items;
+----+---------+--------+--------------+-------------+
| id | name    | rarity | inventory_id | flavor_text |
+----+---------+--------+--------------+-------------+
|  1 | test    | NULL   |         NULL | NULL        |
|  2 | awesome | epic   |         NULL | test        |
+----+---------+--------+--------------+-------------+
2 rows in set (0.00 sec)

[JasonShin]

Released in v0.40.0 https://github.com/JasonShin/sqlx-ts/releases/tag/v0.40.0