migrations, query fixes, fixes for mysql and postgres. In progress

src/EllieBot/Db/EllieContext.cs

@@ -10,6 +10,7 @@ namespace EllieBot.Db;
 public abstract class EllieContext : DbContext
 {
     public DbSet<GuildConfig> GuildConfigs { get; set; }
+    public DbSet<GreetSettings> GreetSettings { get; set; }
 
     public DbSet<Quote> Quotes { get; set; }
     public DbSet<Reminder> Reminders { get; set; }
@@ -678,6 +679,18 @@ public abstract class EllieContext : DbContext
                     .OnDelete(DeleteBehavior.Cascade);
 
         #endregion
+
+        #region GreetSettings
+
+        modelBuilder
+            .Entity<GreetSettings>(gs => gs.HasIndex(x => new
+            {
+                x.GuildId,
+                x.GreetType
+            })
+            .IsUnique());
+
+        #endregion
     }
 
 #if DEBUG