fixes

Author: mbrandonw

Sources/StructuredQueriesCore/Documentation.docc/Articles/QueryCookbook.md

@@ -477,11 +477,15 @@ RemindersList
   .select {
     Row.Columns(
       remindersList: $0,
-      milestones: #sql("\($1.jsonGroupArray(filter: $1.id.isNot(nil))"),
-      reminders: #sql("\($2.jsonGroupArray(filter: $2.id.isNot(nil))")
+      milestones: #sql("\($1.jsonGroupArray(isDistinct: true, filter: $1.id.isNot(nil))"),
+      reminders: #sql("\($2.jsonGroupArray(isDistinct: true, filter: $2.id.isNot(nil))")
     )
   }
 ```
 
+> Note: Because we are now joining two independent tables to `RemindersList`, we will get duplicate
+> entries for all pairs of reminders with milestones. To remove those duplicates we use the 
+> `isDistinct` option for `jsonGroupArray`.
+
 This will now load all reminders lists with all of their reminders and milestones in one single
 SQL query.

Tests/StructuredQueriesTests/JSONFunctionsTests.swift

@@ -214,9 +214,9 @@ extension SnapshotTests {
       assertQuery(
         RemindersList
           .group(by: \.id)
-          .leftJoin(Reminder.incomplete) { $0.id.eq($1.remindersListID) }
           .leftJoin(Milestone.all) { $0.id.eq($2.remindersListID) }
-          .select { remindersList, reminder, milestone in
+          .leftJoin(Reminder.incomplete) { $0.id.eq($1.remindersListID) }
+          .select { remindersList, milestone, reminder in
             RemindersListRow.Columns(
               remindersList: remindersList,
               milestones: #sql(