{
	"comment": "Add tl_target_id on templatelinks (T299418)",
	"before": {
		"name": "templatelinks",
		"comment": "Track template inclusions. The target page may or may not exist, and due to renames and deletions may refer to different page records as time goes by.",
		"columns": [
			{
				"name": "tl_from",
				"comment": "Key to the page_id of the page containing the link.",
				"type": "integer",
				"options": { "notnull": true, "unsigned": true, "default": 0 }
			},
			{
				"name": "tl_from_namespace",
				"type": "integer",
				"comment": "Namespace for this page",
				"options": { "notnull": true, "default": 0 }
			},
			{
				"name": "tl_namespace",
				"type": "integer",
				"options": { "notnull": true, "default": 0 }
			},
			{
				"name": "tl_title",
				"type": "binary",
				"options": { "notnull": true, "length": 255, "default": "" }
			}
		],
		"indexes": [
			{
				"name": "tl_namespace",
				"columns": [ "tl_namespace", "tl_title", "tl_from" ],
				"comment": "Reverse index, for Special:Whatlinkshere",
				"unique": false
			},
			{
				"name": "tl_backlinks_namespace",
				"columns": [ "tl_from_namespace", "tl_namespace", "tl_title", "tl_from" ],
				"comment": "Index for Special:Whatlinkshere with namespace filter",
				"unique": false
			}
		],
		"pk": [ "tl_from", "tl_namespace", "tl_title" ]
	},
	"after": {
		"name": "templatelinks",
		"comment": "Track template inclusions. The target page may or may not exist, and due to renames and deletions may refer to different page records as time goes by.",
		"columns": [
			{
				"name": "tl_from",
				"comment": "Key to the page_id of the page containing the link.",
				"type": "integer",
				"options": { "notnull": true, "unsigned": true, "default": 0 }
			},
			{
				"name": "tl_from_namespace",
				"type": "integer",
				"comment": "Namespace for this page",
				"options": { "notnull": true, "default": 0 }
			},
			{
				"name": "tl_namespace",
				"type": "integer",
				"options": { "notnull": true, "default": 0 }
			},
			{
				"name": "tl_title",
				"type": "binary",
				"options": { "notnull": true, "length": 255, "default": "" }
			},
			{
				"name": "tl_target_id",
				"type": "bigint",
				"comment": "Foreign key to linktarget.lt_id",
				"options": { "notnull": false, "unsigned": true, "default": null }
			}
		],
		"indexes": [
			{
				"name": "tl_namespace",
				"columns": [ "tl_namespace", "tl_title", "tl_from" ],
				"comment": "Reverse index, for Special:Whatlinkshere",
				"unique": false
			},
			{
				"name": "tl_backlinks_namespace",
				"columns": [ "tl_from_namespace", "tl_namespace", "tl_title", "tl_from" ],
				"comment": "Index for Special:Whatlinkshere with namespace filter",
				"unique": false
			},
			{
				"name": "tl_target_id",
				"columns": [ "tl_target_id", "tl_from" ],
				"comment": "Reverse index, for Special:Whatlinkshere",
				"unique": false
			},
			{
				"name": "tl_backlinks_namespace_target_id",
				"columns": [ "tl_from_namespace", "tl_target_id", "tl_from" ],
				"comment": "Index for Special:Whatlinkshere with namespace filter",
				"unique": false
			}
		],
		"pk": [ "tl_from", "tl_namespace", "tl_title" ]
	}
}