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Details for niflheimis

niflheimis has participated in the following threads:

Added by niflheimis on 17 Jun 2022 at 11:23

I have no experience with SQL (yet:)) and I wrote a slightly different code. I didn't want to write multiple selects, and wanted to write one select with inner join. The code works well, but I was wondering which is more practical in general? This one or the one in the answer? 

DECLARE @EpisodeName varchar(100)
DECLARE @EpisodeId int = 42
DECLARE @NumberCompanions int
DECLARE @NumberEnemies int 

SELECT 
    @EpisodeName = Title
    ,@NumberCompanions = COUNT(c.EpisodeId)
    ,@NumberEnemies = COUNT(EnemyID)
    
FROM 
    tblEpisode as e 
        INNER JOIN tblEpisodeCompanion as c
        ON c.EpisodeId = e.EpisodeId
        INNER JOIN tblEpisodeEnemy as n
        ON e.EpisodeId = n.EpisodeId
WHERE
    @EpisodeID = e.EpisodeId
GROUP BY 
    EpisodeNumber
    ,e.Title
    ,e.EpisodeID
SELECT
    @EpisodeName AS Title 
    ,@EpisodeID AS 'Episode id'
    ,@NumberCompanions AS 'Number of companions' 
    ,@NumberEnemies AS 'Number of enemies' 

Added by niflheimis on 16 Feb 2022 at 20:44

Hi,

Why is the parenthesis necessary? I did notice that without it the "AND EventDate >= '19700101'" doesn't work, but I don't understand why. 

I would appreciate an explanation :) 

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