From c934649b91b81a47b7cfe95b79d73cc208c0044c Mon Sep 17 00:00:00 2001
From: SimonLab <simon.labondance@gmail.com>
Date: Wed, 6 Mar 2019 13:09:54 +0000
Subject: [PATCH] use regex instead of String.split to match query terms,
 https://github.com/dwyl/alog/issues/40#issuecomment-470015373

---
 config/test.exs        |  4 ++--
 lib/alog/connection.ex | 25 +++++++++++++++++++++++--
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/config/test.exs b/config/test.exs
index cead70a..47d1f1b 100644
--- a/config/test.exs
+++ b/config/test.exs
@@ -2,8 +2,8 @@ use Mix.Config
 
 config :alog, Alog.Repo,
   username: "postgres",
-  password: "postgres",
-  database: "test_app_dev",
+  password: "docker",
+  database: "routinedb",
   hostname: "localhost",
   pool: Ecto.Adapters.SQL.Sandbox,
   priv: "priv/repo/test_app/"
diff --git a/lib/alog/connection.ex b/lib/alog/connection.ex
index 59b4209..167008f 100644
--- a/lib/alog/connection.ex
+++ b/lib/alog/connection.ex
@@ -68,8 +68,29 @@ defmodule Alog.Connection do
     query
   end
 
-  defp distinct_entry_id("SELECT " <> query) do
-    IO.iodata_to_binary(["SELECT ", "DISTINCT ON (\"entry_id\" ) ", query])
+  # defp distinct_entry_id("SELECT " <> fields <> " FROM " <> table_name <> " AS " <> table_as <> " " <> rest_query) do
+  #
+  #   IO.iodata_to_binary(["SELECT ", "DISTINCT ON (#{table_as}\".entry_id\" ) ", query])
+  # end
+
+  defp distinct_entry_id(query) do
+    query_data = get_query_data(query)
+    if (query_data["table_name"] == "\"schema_migrations\"") do
+      query
+    else
+      IO.iodata_to_binary(
+      [ "SELECT DISTINCT ON (#{query_data["table_as"]}.\"entry_id\" ) ",
+        query_data["fields"],
+        " FROM ",
+        query_data["table_name"], " AS ", query_data["table_as"],
+        query_data["rest_query"]
+    ]
+    )
+    end
+  end
+
+  defp get_query_data(query) do
+    Regex.named_captures(~r/(\bSELECT\b)\s(?<fields>.*)\sFROM\s(?<table_name>.*)\sas\s(?<table_as>.*)(?<rest_query>.*)/i, query)
   end
 
   @impl true