Use delete query format suppored by wpdb::get_table_from_query() in Abstract_WC_Order_Data_Store_CPT::delete_items()

[prettyboymp]

Changes proposed in this Pull Request:

Closes #46639.

This change updates the delete queries for order item meta in Abstract_WC_Order_Data_Store_CPT::delete_items() from the format of DELETE FROM {alias} USING {table} {alias} to a format of DELETE {alias} FROM {table} as {alias}. The former is not a format supported by wpdb::get_table_from_query() in WordPress core, so ::get_table_from_query() instead returns the alias as the table name. This breaks DB extensions like HyperDB that rely on the table name to determine what dataset to query from.

How to test the changes in this Pull Request:

This is difficult to isolate this specific code for testing. One option is to setup a site using HyperDB to route queries in a way that configured to only recognize tables starting with the default wp_ table prefix and attempt to remove order items from an order.

Alternatively, we can validate the queries specifically by duplicating them in a custom unit test that uses the WpdbExposedMethodsForTesting to expose the ::get_table_from_query() method. E.g:

public function test_delete_item_meta_queries() {
	global $wpdb;

	$test_wpdb = new WpdbExposedMethodsForTesting();
	$query = $wpdb->prepare( "DELETE itemmeta FROM {$wpdb->prefix}woocommerce_order_itemmeta as itemmeta INNER JOIN {$wpdb->prefix}woocommerce_order_items as items WHERE itemmeta.order_item_id = items.order_item_id AND items.order_id = %d AND items.order_item_type = %s", 1, 'foo' );
	$actual_table = $test_wpdb->get_table_from_query($query);
	$expected_table = "{$wpdb->prefix}woocommerce_order_itemmeta";
	$this->assertEquals($expected_table, $actual_table);

}

Changelog entry

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Significance

• Patch
• Minor
• Major

Type

• Fix - Fixes an existing bug
• Add - Adds functionality
• Update - Update existing functionality
• Dev - Development related task
• Tweak - A minor adjustment to the codebase
• Performance - Address performance issues
• Enhancement - Improvement to existing functionality

Message Update delete item meta query to format supported by wpdb::get_table_from_query()

Comment

[github-actions]

Hi @vedanshujain,

Apart from reviewing the code changes, please make sure to review the testing instructions as well.

You can follow this guide to find out what good testing instructions should look like:
https://github.com/woocommerce/woocommerce/wiki/Writing-high-quality-testing-instructions

[vedanshujain]

LGTM! Added some unit test around these flows, will merge after CI passes.