Add on delete cascade to sql definition.

highscores_database.sql

@@ -17,7 +17,7 @@ CREATE TABLE CategoryGroups(
    PadLength smallint not null DEFAULT 26,
    UsernameLength smallint DEFAULT 12,
    CONSTRAINT UniqueGuildCategoryGroup UNIQUE (GuildId, GroupName),
-   FOREIGN KEY (GuildId) REFERENCES Guilds(GuildId),
+   FOREIGN KEY (GuildId) REFERENCES Guilds(GuildId) ON DELETE CASCADE,
    PRIMARY KEY (GroupId)
 );
 
@@ -30,7 +30,7 @@ CREATE TABLE Categories(
    IsTimeRecord boolean not null DEFAULT false,
    IsValidated boolean not null DEFAULT true,
    CONSTRAINT UniqueCategoryInGroup UNIQUE (GroupId, CategoryName),
-   FOREIGN KEY (GroupId) REFERENCES CategoryGroups(GroupId),
+   FOREIGN KEY (GroupId) REFERENCES CategoryGroups(GroupId) ON DELETE CASCADE,
    PRIMARY Key (CategoryId)
 );
 
@@ -38,6 +38,6 @@ CREATE TABLE Scores(
    UserName varchar(30) not null,
    Score float not null, -- Maybe should have time and int scores?? timestamp type?
    CategoryId int unsigned not null,
-   FOREIGN KEY (CategoryId) REFERENCES Categories(CategoryId),
+   FOREIGN KEY (CategoryId) REFERENCES Categories(CategoryId) ON DELETE CASCADE,
    PRIMARY KEY (CategoryId, UserName)
 );