How to get a child table records which exist in results of a table valued function - sql

Question

I have a table named TBL_WorkOrder as below :
+----+------------+----------------+
| Id | SystemCode | WorkOrderTitle |
+----+------------+----------------+
| 1 | C001 | Title 1 |
| 2 | C002 | Title 2 |
| 3 | C003 | Title 3 |
+----+------------+----------------+
and another table named TBL_WorkGroup
+----+---------------+
| Id | WorkGroupName |
+----+---------------+
| 1 | WorkGroup1 |
| 2 | WorkGroup2 |
| 3 | WorkGroup3 |
+----+---------------+
Each work order can contain different work groups as below (TBL_WorkOrderGroup)
+----+-------------+-------------+
| Id | WorkOrderId | WorkGroupId |
+----+-------------+-------------+
| 1 | 1 | 1 |
| 2 | 1 | 3 |
| 3 | 2 | 1 |
+----+-------------+-------------+
The problem is that I send a varchar string like '1,3' to the stored procedure. This varchar is changed to a table using a table valued function. I want to obtain the work orders that contain both '1' and '3' as their work groups.
What should i do in this case?

Answer 1

DECLARE #String VARCHAR(100) = '1,3'
;WITH Split AS
(
SELECT SUBSTRING(#String,0,CHARINDEX(',',#String)) SplitStr,SUBSTRING(#String,CHARINDEX(',',#String)+1,LEN(#String)) RemainStr
UNION ALL
SELECT CASE WHEN CHARINDEX(',',RemainStr) = 0 THEN RemainStr ELSE SUBSTRING(RemainStr,0,CHARINDEX(',',RemainStr)) END,
CASE WHEN CHARINDEX(',',RemainStr) = 0 THEN '' ELSE SUBSTRING(RemainStr,CHARINDEX(',',RemainStr)+1,LEN(RemainStr)) END
FROM Split
WHERE ISNULL(RemainStr,'') <> ''
)
SELECT SplitStr FROM Split