I've created a simple example (hopefully much more fun than my actual data) to better express my question:
CREATE TABLE SUPER_HERO
( ID INT,
NAME VARCHAR(50)
)
INSERT INTO SUPER_HERO VALUES (1, 'Storm')
INSERT INTO SUPER_HERO VALUES (2, 'Silver Surfer')
INSERT INTO SUPER_HERO VALUES (3, 'Spider Man')
CREATE TABLE SKILL
( ID INT,
NAME VARCHAR(50)
)
INSERT INTO SKILL VALUES (1, 'Flight')
INSERT INTO SKILL VALUES (2, 'Weather Control')
INSERT INTO SKILL VALUES (3, 'Super Speed')
CREATE TABLE SUPER_HERO_SKILL
( SUPER_HERO_ID INT,
SKILL_ID INT
)
INSERT INTO SUPER_HERO_SKILL VALUES (1, 1) --Storm has Flight
INSERT INTO SUPER_HERO_SKILL VALUES (1, 2) --Storm has Weather Control
INSERT INTO SUPER_HERO_SKILL VALUES (2, 1) --Silver Surfer has Flight
INSERT INTO SUPER_HERO_SKILL VALUES (2, 3) --Silver Surfer has Super Speed
INSERT INTO SUPER_HERO_SKILL VALUES (3, 3) --Spider Man has Super Speed
Example of bad query (not showing desired results):
DECLARE @DELIMITER CHAR = ','
DECLARE @CSV_STRING VARCHAR(20) = '1,3'
SELECT
SUPER_HERO_NAME = SUPER_HERO.NAME,
SKILL_NAME = SKILL.NAME
FROM
SUPER_HERO
JOIN SUPER_HERO_SKILL ON SUPER_HERO_SKILL.SUPER_HERO_ID = SUPER_HERO.ID
JOIN SKILL ON SUPER_HERO_SKILL.SKILL_ID = SKILL.ID
JOIN dbo.Split(@CSV_STRING, @DELIMITER) SPLIT ON SPLIT.ITEMS = SKILL.ID
What I would like to see:
When DECLARE @CSV_STRING VARCHAR(20) = '1,3'
I should only see "Silver Surfer" since he is the only one with both skills 1 and 3 which correlate to Flight and Super Speed.
When DECLARE @CSV_STRING VARCHAR(20) = '1,2,3'
I should not see any heroes in my universe since there are none defined to have all three skills listed.
There must be something simple that I am missing. I have tried structuring the query many different ways. I have presented the simplest form of it here as not to complicate the presentation of problem.
Note: I use a function that acts as a Split based on delimiter passed in.
The SQL EXCEPT operator is used to return all rows in the first SELECT statement that are not returned by the second SELECT statement. Each SELECT statement will define a dataset. The EXCEPT operator will retrieve all records from the first dataset and then remove from the results all records from the second dataset.
To check if value exists in a comma separated list, you can use FIND_IN_SET() function. Now you can insert some records in the table using insert command. Display all records from the table using select statement.
To select rows using selection symbols for character or graphic data, use the LIKE keyword in a WHERE clause, and the underscore and percent sign as selection symbols. You can create multiple row conditions, and use the AND, OR, or IN keywords to connect the conditions.
Use the below splitter function which returns an int column. So it's easy to check the count in the HAVING clause.
CREATE FUNCTION [dbo].[DelimitedParamParser]( @DelimitedIds VARCHAR(MAX), @Delimiter CHAR(1))
RETURNS @IdsTable
TABLE ( Id INT )
AS BEGIN
DECLARE @Length INT,
@Index INT,
@NextIndex INT
SET @Length = DATALENGTH(@DelimitedIds)
SET @Index = 0
SET @NextIndex = 0
WHILE (@Length > @Index )
BEGIN
SET @NextIndex = CHARINDEX(@Delimiter, @DelimitedIds, @Index)
IF (@NextIndex = 0 ) SET @NextIndex = @Length + 2
INSERT @IdsTable SELECT SUBSTRING( @DelimitedIds, @Index, @NextIndex - @Index )
SET @index = @nextindex + 1
END
RETURN
END
This works, keep in mind to give an extra comma at the end.
DECLARE @DELIMITER CHAR = ','
DECLARE @CSV_STRING VARCHAR(20) = '1,3,'
SELECT Distinct SUPER_HERO.NAME, SKILL.NAME
FROM
SUPER_HERO
INNER JOIN SUPER_HERO_SKILL ON SUPER_HERO_SKILL.SUPER_HERO_ID = SUPER_HERO.ID
INNER JOIN SKILL ON SUPER_HERO_SKILL.SKILL_ID = SKILL.ID
WHERE SUPER_HERO.ID IN
(
SELECT SUPER_HERO_SKILL.SUPER_HERO_ID
FROM
SUPER_HERO
INNER JOIN SUPER_HERO_SKILL ON SUPER_HERO_SKILL.SUPER_HERO_ID = SUPER_HERO.ID
INNER JOIN SKILL ON SUPER_HERO_SKILL.SKILL_ID = SKILL.ID
INNER JOIN DelimitedParamParser(@CSV_STRING, @DELIMITER) SPLIT ON SPLIT.ID = SUPER_HERO_SKILL.SKILL_ID
GROUP BY SUPER_HERO_SKILL.SUPER_HERO_ID
HAVING COUNT(DISTINCT(SUPER_HERO_SKILL.SKILL_ID)) = (SELECT COUNT(DISTINCT(Id)) FROM DelimitedParamParser(@CSV_STRING, @DELIMITER))
)
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With