From 7cbc1103dec12bc49938ce73d94273ce21789786 Mon Sep 17 00:00:00 2001
From: jsmith <publicjs@tutanota.com>
Date: Thu, 15 Apr 2021 10:42:40 +0000
Subject: [PATCH] auditskis.sql

---
 PostgreSQL/audittrigger.sql | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 PostgreSQL/audittrigger.sql

diff --git a/PostgreSQL/audittrigger.sql b/PostgreSQL/audittrigger.sql
new file mode 100644
index 0000000..7aa6c17
--- /dev/null
+++ b/PostgreSQL/audittrigger.sql
@@ -0,0 +1,28 @@
+CREATE TABLE generic_log (
+  mtime timestamptz not null default now(),
+  action char not null check (action in ('I', 'U', 'D')),
+  username text not null,
+  table_name text not null,
+  row_data jsonb not null
+);
+ 
+CREATE INDEX ON generic_log USING brin (mtime);
+CREATE INDEX ON generic_log ((row_data->>'my_pk’)) WHERE row_data->>'my_pk' IS NOT NULL;  // note the cast to text as JSONB can’t be indexed with B-tree
+CREATE EXTENSION IF NOT EXISTS btree_gin;
+CREATE INDEX ON generic_log USING gin (table_name);  // GiN is better for lots of repeating values
+ 
+ 
+CREATE OR REPLACE FUNCTION public.generic_log_trigger()
+ RETURNS trigger LANGUAGE plpgsql
+AS $function$
+BEGIN
+  IF TG_OP = 'DELETE' THEN
+    INSERT INTO generic_log VALUES (now(), 'D', session_user, TG_TABLE_NAME, to_json(OLD));
+  ELSE
+    INSERT INTO generic_log VALUES (now(), TG_OP::char , session_user, TG_TABLE_NAME, to_json(NEW));
+  END IF;
+  RETURN NULL;
+END;
+$function$;
+ 
+CREATE TRIGGER log_generic AFTER INSERT OR UPDATE OR DELETE ON some_table FOR EACH ROW EXECUTE FUNCTION generic_log_trigger();
\ No newline at end of file