SQL-Syntax Optimierung (Distinct, Verknüpfung)

[mkinzler]

Hier mal als expliziter Join

SQL-Code:

SELECT 
    distinct g.ID, g.Description
FROM 
    Groups g 
        join Templates t on t.GroupID = g.GroupID
WHERE 
    t.FormID = :FormId;

Alternativ wäre ein Gruppierung

SQL-Code:

SELECT 
    g.ID, g.Description
FROM 
    Groups g 
        join Templates t on t.GroupID = g.GroupID
WHERE 
    t.FormID = :FormId
grooup by 
    g.ID, g.Description;

oder ein Subselect denkbar:

SQL-Code:

SELECT 
    g.ID, g.Description
FROM 
    Groups g 
where
    g.GroupID in ( select distinct GroupID from Templates);

bzw.

SQL-Code:

SELECT 
    g.ID, g.Description
FROM 
    Groups g 
where
    exists ( select distinct t.GroupID from Templates where t.GroupId = g.GroupID);