optimize chat filtering/searching

Data/Migrations/Postgresql/20220616224145_AddDescendingTimeSentIndexEFClientMessages.cs

@@ -0,0 +1,24 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace Data.Migrations.Postgresql
+{
+    public partial class AddDescendingTimeSentIndexEFClientMessages : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.Sql(
+                @"CREATE INDEX""IX_EFClientMessages_TimeSentDesc""
+                ON public.""EFClientMessages"" USING btree
+                (""TimeSent"" DESC NULLS LAST)
+                TABLESPACE pg_default;"
+            );
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.Sql(@"DROP INDEX public.""IX_EFClientMessages_TimeSentDesc""");
+        }
+    }
+}