diff --git a/.gitignore b/.gitignore
index 182fcdc..eda4284 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,4 +2,5 @@
 schedoc.control
 *.zip
 test/sql/*.sql
-test/*.sql
\ No newline at end of file
+test/*.sql
+exclude.sql
diff --git a/Makefile b/Makefile
index 2914cb8..16b307a 100644
--- a/Makefile
+++ b/Makefile
@@ -7,6 +7,8 @@ INTETESTS = $(shell find test/ -type f -name '*.sql.in' | sed -e 's/.in$$//')
 
 EXTENSION = schedoc
 
+TOOLSEXC = $(wildcard tools_exclusion/*.sql)
+
 EXTVERSION   = $(shell grep -m 1 '[[:space:]]\{3\}"version":' META.json | \
 	       sed -e 's/[[:space:]]*"version":[[:space:]]*"\([^"]*\)",\{0,1\}/\1/')
 
@@ -29,24 +31,31 @@ include $(PGXS)
 all: $(DIST) $(PGTLEOUT) $(EXTENSION).control $(UNITTESTS) $(INTETESTS)
 
 clean:
-	rm -f $(PGTLEOUT) $(DIST) $(UNITTESTS)
+	rm -f $(PGTLEOUT) $(DIST) $(UNITTESTS) exclude.sql
 
-$(DIST): $(FILES)
+$(DIST): $(FILES) exclude.sql
 	cat sql/table.sql > $@
+	cat sql/management.sql >> $@
 	cat sql/function.sql >> $@
 	cat sql/function-stop.sql >> $@
 	cat sql/function-status.sql >> $@
+	cat sql/view.sql >> $@
+	cat exclude.sql >> $@
 	cat sql/start.sql >> $@
 	cat $@ > dist/$(EXTENSION).sql
 
-test:
+exclude.sql: $(TOOLSEXC)
+	cat $(TOOLSEXC) > exclude.sql
+
+test: $(UNITTESTS) $(INTETESTS)
 	pg_prove -f test/sql/*.sql
 
 test/sql/%.sql: test/sql/%.sql.in
 	sed 's,_TEST_SCHEMA_,$(TEST_SCHEMA),g; ' $< > $@
 
 test/%.sql: test/%.sql.in
-	sed 's,_TEST_SCHEMA_,$(TEST_SCHEMA),g; ' $< > $@
+	echo "--\n-- Auto generated file DO NOT EDIT !!" > $@
+	sed 's,_TEST_SCHEMA_,$(TEST_SCHEMA),g; ' $< >> $@
 
 $(PGTLEOUT): dist/$(EXTENSION)--$(EXTVERSION).sql pgtle_header.in pgtle_footer.in
 	sed -e 's/_EXTVERSION_/$(EXTVERSION)/' pgtle_header.in > $(PGTLEOUT)
diff --git a/dist/pgtle.schedoc--0.0.2.sql b/dist/pgtle.schedoc--0.0.2.sql
index ae235ce..84b66a5 100644
--- a/dist/pgtle.schedoc--0.0.2.sql
+++ b/dist/pgtle.schedoc--0.0.2.sql
@@ -54,16 +54,129 @@ CREATE TABLE @extschema@.schedoc_column_log (
 --
 --
 --
+CREATE TABLE @extschema@.schedoc_table_exclusion (
+  schema_name name,
+  table_name name,
+  tag text,
+  created_at timestamp with time zone DEFAULT current_timestamp,
+  created_by text DEFAULT current_user,
+  PRIMARY KEY (schema_name, table_name)
+);
 
-CREATE VIEW @extschema@.schedoc_column_comments AS
+CREATE TABLE @extschema@.schedoc_table_exclusion_templates (
+  schema_name name,
+  table_name name,
+  tags text[],
+  created_at timestamp with time zone DEFAULT current_timestamp,
+  created_by text DEFAULT current_user,
+  PRIMARY KEY (schema_name, table_name)
+);
 
-    SELECT current_database() as databasename, c.relname as tablename, a.attname as columnname, status
-    FROM schedoc_column_raw ccr
-    JOIN pg_class c ON c.oid = ccr.objoid
-    JOIN pg_attribute a ON (a.attnum = ccr.objsubid AND a.attrelid = ccr.objoid);
+--
+--
+--
+--
+-- schedoc_exclude_tool(tool text)
+-- schedoc_exclude_tools_all()
+-- schedoc_is_table_excluded(tableoid oid)
+--
+-- Set up the exclusion list
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_exclude_tool(tool text)
+RETURNS text
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  nbrows bigint;
+BEGIN
+   --
+   --
+   --
+   INSERT INTO @extschema@.schedoc_table_exclusion (schema_name, table_name, tag)
+   SELECT schema_name, table_name, tool FROM @extschema@.schedoc_table_exclusion_templates
+   WHERE tags @> ARRAY[tool];
+
+   SELECT count(1) FROM @extschema@.schedoc_table_exclusion WHERE tag = tool INTO nbrows;
+
+   RETURN format ('Inserted %s row(s) in schedoc_table_exclusion', nbrows);
+END;
+$EOF$;
+--
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_exclude_tools_all()
+RETURNS text
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  nbrows bigint;
+BEGIN
+   --
+   --
+   --
+   INSERT INTO @extschema@.schedoc_table_exclusion (schema_name, table_name, tag)
+   SELECT schema_name, table_name, tags[0] FROM @extschema@.schedoc_table_exclusion_templates;
 
+   SELECT count(1) FROM @extschema@.schedoc_table_exclusion INTO nbrows;
+
+   RETURN format ('Inserted %s row(s) in schedoc_table_exclusion', nbrows);
+END;
+$EOF$;
+--
+-- Check if a table is present in the exclusion list
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_is_table_excluded(tableoid oid)
+RETURNS boolean
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  status boolean;
+BEGIN
+    WITH
+    excluded AS (
+      SELECT c.oid
+      FROM pg_class c
+      JOIN @extschema@.schedoc_table_exclusion ste ON ste.table_name = c.relname
+      JOIN pg_namespace n ON (n.oid = c.relnamespace AND n.nspname = ste.schema_name)
+    ),
+    internals AS (
+      SELECT oid FROM excluded
+      UNION
+      SELECT c.oid FROM pg_class c
+      JOIN pg_namespace n ON (n.oid = c.relnamespace)
+      WHERE relname IN (
+            'ddl_history',
+            'ddl_history_column',
+            'ddl_history_schema',
+            'schedoc_column_log',
+            'schedoc_column_raw',
+            'schedoc_table_exclusion',
+            'schedoc_table_exclusion_templates',
+            'schedoc_valid',
+            'schedoc_valid_status')
+            AND n.nspname = '@extschema@'
+     )
+     SELECT count(1) > 0 FROM internals WHERE oid = tableoid INTO status;
+
+     RETURN status;
+END;
+$EOF$;
+--
 --
 --
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_init_existing_comments()
+RETURNS void
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  status boolean;
+BEGIN
+
+    PERFORM @extschema@.schedoc_fill_raw(objoid, objsubid)
+    FROM @extschema@.schedoc_column_existing_comments
+    WHERE description IS NOT NULL;
+
+END;
+$EOF$;
 --
 --
 --
@@ -75,47 +188,13 @@ BEGIN
    --
    -- Function to manage INSERT statements
    --
+   -- This function is called by a trigger on ddl_history
    CREATE OR REPLACE FUNCTION @extschema@.schedoc_trg()
         RETURNS trigger LANGUAGE plpgsql AS $fsub$
     BEGIN
 
-    -- keep a log of all values
-    INSERT INTO @extschema@.schedoc_column_log (objoid, objsubid, comment, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid),
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    );
-
+    PERFORM @extschema@.schedoc_fill_raw(NEW.objoid, NEW.objsubid);
 
-   -- if the json is valid
-   IF schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON THEN
-    INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, comment, status, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid)::jsonb,
-      @extschema@.schedoc_get_column_status(NEW.objoid, NEW.objsubid)::@extschema@.schedoc_status,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    ) ON CONFLICT (objoid, objsubid)
-    DO UPDATE SET
-      comment = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid)::jsonb,
-      status = @extschema@.schedoc_get_column_status(EXCLUDED.objoid, EXCLUDED.objsubid)::@extschema@.schedoc_status,
-      is_valid = @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON;
-    ELSE
-    --
-    -- This is not a valid json, we store it
-    --
-    INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    ) ON CONFLICT (objoid, objsubid)
-    DO UPDATE SET
-      is_valid = @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON;
-    END IF;
     RETURN NEW;
     END;
     $fsub$;
@@ -129,6 +208,7 @@ BEGIN
     BEGIN
     --
     --
+    IF NOT @extschema@.schedoc_is_table_excluded(NEW.attrelid) THEN
     INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
     VALUES (
       NEW.attrelid,
@@ -137,7 +217,7 @@ BEGIN
     ) ON CONFLICT (objoid, objsubid)
     DO UPDATE SET
       is_valid = false;
-
+    END IF;
     RETURN NEW;
     END;
     $fsub$;
@@ -163,6 +243,58 @@ BEGIN
 
 END;
 $EOF$;
+--
+-- schedoc_fill_raw
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_fill_raw(p_oid oid, p_subid oid)
+RETURNS void
+    LANGUAGE plpgsql AS
+$EOF$
+BEGIN
+    --
+    --
+    -- keep a log of all values
+    INSERT INTO @extschema@.schedoc_column_log (objoid, objsubid, comment, is_valid)
+    VALUES (
+        p_oid,
+        p_subid,
+        @extschema@.schedoc_get_column_description(p_oid, p_subid),
+        @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+    );
+
+    IF NOT @extschema@.schedoc_is_table_excluded(p_oid) THEN
+       -- if the json is valid
+       IF schedoc_get_column_description(p_oid, p_subid) IS JSON THEN
+          INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, comment, status, is_valid)
+          VALUES (
+             p_oid,
+             p_subid,
+             @extschema@.schedoc_get_column_description(p_oid, p_subid)::jsonb,
+             @extschema@.schedoc_get_column_status(p_oid, p_subid)::@extschema@.schedoc_status,
+             @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+          ) ON CONFLICT (objoid, objsubid)
+          DO UPDATE SET
+             comment = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid)::jsonb,
+             status = @extschema@.schedoc_get_column_status(EXCLUDED.objoid, EXCLUDED.objsubid)::@extschema@.schedoc_status,
+             is_valid = @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON;
+       ELSE
+           --
+           -- This is not a valid json, we store it
+           --
+           INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
+           VALUES (
+               p_oid,
+               p_subid,
+               @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+           ) ON CONFLICT (objoid, objsubid)
+           DO UPDATE SET
+               is_valid = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid) IS JSON;
+       END IF;
+    END IF;
+END;
+$EOF$;
+
+
 
 --
 --
@@ -238,6 +370,111 @@ BEGIN
 END;
 $EOF$;
 --
+--
+--
+
+CREATE VIEW schedoc_column_comments AS
+
+    SELECT current_database() as databasename, c.relname as tablename, a.attname as columnname, status
+    FROM schedoc_column_raw ccr
+    JOIN pg_class c ON c.oid = ccr.objoid
+    JOIN pg_attribute a ON (a.attnum = ccr.objsubid AND a.attrelid = ccr.objoid);
+--
+--
+--
+CREATE OR REPLACE VIEW schedoc_object_tables AS
+
+    SELECT n.nspname, c.relname
+    FROM pg_depend d
+    JOIN pg_class c ON c.oid = d.objid
+    JOIN pg_namespace n ON n.oid = c.relnamespace
+    JOIN pg_extension e ON e.oid = d.refobjid
+    WHERE e.extname in ('schedoc', 'ddl_historization')
+    AND c.relkind = 'r';
+--
+--
+--
+DROP VIEW IF EXISTS schedoc_column_existing_comments;
+CREATE OR REPLACE VIEW schedoc_column_existing_comments AS
+
+    WITH descr AS (
+      SELECT c.oid as objoid, d.objsubid, c.relname, d.description
+      FROM pg_class c
+      JOIN pg_namespace n ON n.oid = c.relnamespace
+      LEFT JOIN pg_description d ON d.objoid = c.oid
+      LEFT JOIN schedoc_table_exclusion e ON  e.table_name = c.relname
+      WHERE c.relkind = 'r' AND n.nspname='public'
+      AND  e.table_name IS NULL
+      AND c.relname NOT IN (
+            SELECT relname FROM @extschema@.schedoc_object_tables)
+    )
+    SELECT objoid, objsubid, relname, description, description IS NOT NULL AND  description IS JSON as is_ok
+    FROM descr
+
+ORDER BY relname
+;
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'celery_results_taskresult', ARRAY['celery']),
+('public', 'celery_taskmeta', ARRAY['celery']),
+('public', 'celery_tasksetmeta', ARRAY['celery']),
+
+('public', 'djcelery_crontabschedule', ARRAY['celery']),
+('public', 'djcelery_intervalschedule', ARRAY['celery']),
+('public', 'djcelery_periodictask', ARRAY['celery']),
+('public', 'djcelery_taskstate', ARRAY['celery']),
+('public', 'djcelery_workerstate', ARRAY['celery']);
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'dbz_signal', ARRAY['debezium']),
+('public', 'dbz_heartbeat', ARRAY['debezium']);
+--
+-- Exclude tables created by Django Framework
+--
+-- https://www.djangoproject.com/
+--
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+('public', 'auth_group', ARRAY['django']),
+('public', 'auth_group_permissions', ARRAY['django']),
+('public', 'auth_permission', ARRAY['django']),
+('public', 'auth_user', ARRAY['django']),
+('public', 'auth_user_groups', ARRAY['django']),
+('public', 'auth_user_user_permissions', ARRAY['django']),
+('public', 'django_admin_log', ARRAY['django']),
+('public', 'django_content_type', ARRAY['django']),
+('public', 'django_migrations', ARRAY['django']),
+('public', 'django_session', ARRAY['django']);
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'procrastinate_events', ARRAY['procrastinate']),
+('public', 'procrastinate_jobs', ARRAY['procrastinate']),
+('public', 'procrastinate_periodic_defers', ARRAY['procrastinate']);
+--
+--
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'tastypie_apiaccess', ARRAY['tastypie']),
+('public', 'tastypie_apikey', ARRAY['tastypie']);
+--
 -- Check the schema of installation for schedoc
 --
 DO
@@ -254,5 +491,7 @@ END IF;
 
 END;
 $check_start$;
+--
+--
 $_pg_tle_$
 );
diff --git a/dist/schedoc--0.0.2.sql b/dist/schedoc--0.0.2.sql
index ff3bf01..40b8029 100644
--- a/dist/schedoc--0.0.2.sql
+++ b/dist/schedoc--0.0.2.sql
@@ -48,16 +48,129 @@ CREATE TABLE @extschema@.schedoc_column_log (
 --
 --
 --
+CREATE TABLE @extschema@.schedoc_table_exclusion (
+  schema_name name,
+  table_name name,
+  tag text,
+  created_at timestamp with time zone DEFAULT current_timestamp,
+  created_by text DEFAULT current_user,
+  PRIMARY KEY (schema_name, table_name)
+);
 
-CREATE VIEW @extschema@.schedoc_column_comments AS
+CREATE TABLE @extschema@.schedoc_table_exclusion_templates (
+  schema_name name,
+  table_name name,
+  tags text[],
+  created_at timestamp with time zone DEFAULT current_timestamp,
+  created_by text DEFAULT current_user,
+  PRIMARY KEY (schema_name, table_name)
+);
 
-    SELECT current_database() as databasename, c.relname as tablename, a.attname as columnname, status
-    FROM schedoc_column_raw ccr
-    JOIN pg_class c ON c.oid = ccr.objoid
-    JOIN pg_attribute a ON (a.attnum = ccr.objsubid AND a.attrelid = ccr.objoid);
+--
+--
+--
+--
+-- schedoc_exclude_tool(tool text)
+-- schedoc_exclude_tools_all()
+-- schedoc_is_table_excluded(tableoid oid)
+--
+-- Set up the exclusion list
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_exclude_tool(tool text)
+RETURNS text
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  nbrows bigint;
+BEGIN
+   --
+   --
+   --
+   INSERT INTO @extschema@.schedoc_table_exclusion (schema_name, table_name, tag)
+   SELECT schema_name, table_name, tool FROM @extschema@.schedoc_table_exclusion_templates
+   WHERE tags @> ARRAY[tool];
+
+   SELECT count(1) FROM @extschema@.schedoc_table_exclusion WHERE tag = tool INTO nbrows;
+
+   RETURN format ('Inserted %s row(s) in schedoc_table_exclusion', nbrows);
+END;
+$EOF$;
+--
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_exclude_tools_all()
+RETURNS text
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  nbrows bigint;
+BEGIN
+   --
+   --
+   --
+   INSERT INTO @extschema@.schedoc_table_exclusion (schema_name, table_name, tag)
+   SELECT schema_name, table_name, tags[0] FROM @extschema@.schedoc_table_exclusion_templates;
 
+   SELECT count(1) FROM @extschema@.schedoc_table_exclusion INTO nbrows;
+
+   RETURN format ('Inserted %s row(s) in schedoc_table_exclusion', nbrows);
+END;
+$EOF$;
+--
+-- Check if a table is present in the exclusion list
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_is_table_excluded(tableoid oid)
+RETURNS boolean
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  status boolean;
+BEGIN
+    WITH
+    excluded AS (
+      SELECT c.oid
+      FROM pg_class c
+      JOIN @extschema@.schedoc_table_exclusion ste ON ste.table_name = c.relname
+      JOIN pg_namespace n ON (n.oid = c.relnamespace AND n.nspname = ste.schema_name)
+    ),
+    internals AS (
+      SELECT oid FROM excluded
+      UNION
+      SELECT c.oid FROM pg_class c
+      JOIN pg_namespace n ON (n.oid = c.relnamespace)
+      WHERE relname IN (
+            'ddl_history',
+            'ddl_history_column',
+            'ddl_history_schema',
+            'schedoc_column_log',
+            'schedoc_column_raw',
+            'schedoc_table_exclusion',
+            'schedoc_table_exclusion_templates',
+            'schedoc_valid',
+            'schedoc_valid_status')
+            AND n.nspname = '@extschema@'
+     )
+     SELECT count(1) > 0 FROM internals WHERE oid = tableoid INTO status;
+
+     RETURN status;
+END;
+$EOF$;
+--
 --
 --
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_init_existing_comments()
+RETURNS void
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  status boolean;
+BEGIN
+
+    PERFORM @extschema@.schedoc_fill_raw(objoid, objsubid)
+    FROM @extschema@.schedoc_column_existing_comments
+    WHERE description IS NOT NULL;
+
+END;
+$EOF$;
 --
 --
 --
@@ -69,47 +182,13 @@ BEGIN
    --
    -- Function to manage INSERT statements
    --
+   -- This function is called by a trigger on ddl_history
    CREATE OR REPLACE FUNCTION @extschema@.schedoc_trg()
         RETURNS trigger LANGUAGE plpgsql AS $fsub$
     BEGIN
 
-    -- keep a log of all values
-    INSERT INTO @extschema@.schedoc_column_log (objoid, objsubid, comment, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid),
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    );
-
+    PERFORM @extschema@.schedoc_fill_raw(NEW.objoid, NEW.objsubid);
 
-   -- if the json is valid
-   IF schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON THEN
-    INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, comment, status, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid)::jsonb,
-      @extschema@.schedoc_get_column_status(NEW.objoid, NEW.objsubid)::@extschema@.schedoc_status,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    ) ON CONFLICT (objoid, objsubid)
-    DO UPDATE SET
-      comment = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid)::jsonb,
-      status = @extschema@.schedoc_get_column_status(EXCLUDED.objoid, EXCLUDED.objsubid)::@extschema@.schedoc_status,
-      is_valid = @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON;
-    ELSE
-    --
-    -- This is not a valid json, we store it
-    --
-    INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    ) ON CONFLICT (objoid, objsubid)
-    DO UPDATE SET
-      is_valid = @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON;
-    END IF;
     RETURN NEW;
     END;
     $fsub$;
@@ -123,6 +202,7 @@ BEGIN
     BEGIN
     --
     --
+    IF NOT @extschema@.schedoc_is_table_excluded(NEW.attrelid) THEN
     INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
     VALUES (
       NEW.attrelid,
@@ -131,7 +211,7 @@ BEGIN
     ) ON CONFLICT (objoid, objsubid)
     DO UPDATE SET
       is_valid = false;
-
+    END IF;
     RETURN NEW;
     END;
     $fsub$;
@@ -157,6 +237,58 @@ BEGIN
 
 END;
 $EOF$;
+--
+-- schedoc_fill_raw
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_fill_raw(p_oid oid, p_subid oid)
+RETURNS void
+    LANGUAGE plpgsql AS
+$EOF$
+BEGIN
+    --
+    --
+    -- keep a log of all values
+    INSERT INTO @extschema@.schedoc_column_log (objoid, objsubid, comment, is_valid)
+    VALUES (
+        p_oid,
+        p_subid,
+        @extschema@.schedoc_get_column_description(p_oid, p_subid),
+        @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+    );
+
+    IF NOT @extschema@.schedoc_is_table_excluded(p_oid) THEN
+       -- if the json is valid
+       IF schedoc_get_column_description(p_oid, p_subid) IS JSON THEN
+          INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, comment, status, is_valid)
+          VALUES (
+             p_oid,
+             p_subid,
+             @extschema@.schedoc_get_column_description(p_oid, p_subid)::jsonb,
+             @extschema@.schedoc_get_column_status(p_oid, p_subid)::@extschema@.schedoc_status,
+             @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+          ) ON CONFLICT (objoid, objsubid)
+          DO UPDATE SET
+             comment = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid)::jsonb,
+             status = @extschema@.schedoc_get_column_status(EXCLUDED.objoid, EXCLUDED.objsubid)::@extschema@.schedoc_status,
+             is_valid = @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON;
+       ELSE
+           --
+           -- This is not a valid json, we store it
+           --
+           INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
+           VALUES (
+               p_oid,
+               p_subid,
+               @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+           ) ON CONFLICT (objoid, objsubid)
+           DO UPDATE SET
+               is_valid = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid) IS JSON;
+       END IF;
+    END IF;
+END;
+$EOF$;
+
+
 
 --
 --
@@ -232,6 +364,111 @@ BEGIN
 END;
 $EOF$;
 --
+--
+--
+
+CREATE VIEW schedoc_column_comments AS
+
+    SELECT current_database() as databasename, c.relname as tablename, a.attname as columnname, status
+    FROM schedoc_column_raw ccr
+    JOIN pg_class c ON c.oid = ccr.objoid
+    JOIN pg_attribute a ON (a.attnum = ccr.objsubid AND a.attrelid = ccr.objoid);
+--
+--
+--
+CREATE OR REPLACE VIEW schedoc_object_tables AS
+
+    SELECT n.nspname, c.relname
+    FROM pg_depend d
+    JOIN pg_class c ON c.oid = d.objid
+    JOIN pg_namespace n ON n.oid = c.relnamespace
+    JOIN pg_extension e ON e.oid = d.refobjid
+    WHERE e.extname in ('schedoc', 'ddl_historization')
+    AND c.relkind = 'r';
+--
+--
+--
+DROP VIEW IF EXISTS schedoc_column_existing_comments;
+CREATE OR REPLACE VIEW schedoc_column_existing_comments AS
+
+    WITH descr AS (
+      SELECT c.oid as objoid, d.objsubid, c.relname, d.description
+      FROM pg_class c
+      JOIN pg_namespace n ON n.oid = c.relnamespace
+      LEFT JOIN pg_description d ON d.objoid = c.oid
+      LEFT JOIN schedoc_table_exclusion e ON  e.table_name = c.relname
+      WHERE c.relkind = 'r' AND n.nspname='public'
+      AND  e.table_name IS NULL
+      AND c.relname NOT IN (
+            SELECT relname FROM @extschema@.schedoc_object_tables)
+    )
+    SELECT objoid, objsubid, relname, description, description IS NOT NULL AND  description IS JSON as is_ok
+    FROM descr
+
+ORDER BY relname
+;
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'celery_results_taskresult', ARRAY['celery']),
+('public', 'celery_taskmeta', ARRAY['celery']),
+('public', 'celery_tasksetmeta', ARRAY['celery']),
+
+('public', 'djcelery_crontabschedule', ARRAY['celery']),
+('public', 'djcelery_intervalschedule', ARRAY['celery']),
+('public', 'djcelery_periodictask', ARRAY['celery']),
+('public', 'djcelery_taskstate', ARRAY['celery']),
+('public', 'djcelery_workerstate', ARRAY['celery']);
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'dbz_signal', ARRAY['debezium']),
+('public', 'dbz_heartbeat', ARRAY['debezium']);
+--
+-- Exclude tables created by Django Framework
+--
+-- https://www.djangoproject.com/
+--
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+('public', 'auth_group', ARRAY['django']),
+('public', 'auth_group_permissions', ARRAY['django']),
+('public', 'auth_permission', ARRAY['django']),
+('public', 'auth_user', ARRAY['django']),
+('public', 'auth_user_groups', ARRAY['django']),
+('public', 'auth_user_user_permissions', ARRAY['django']),
+('public', 'django_admin_log', ARRAY['django']),
+('public', 'django_content_type', ARRAY['django']),
+('public', 'django_migrations', ARRAY['django']),
+('public', 'django_session', ARRAY['django']);
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'procrastinate_events', ARRAY['procrastinate']),
+('public', 'procrastinate_jobs', ARRAY['procrastinate']),
+('public', 'procrastinate_periodic_defers', ARRAY['procrastinate']);
+--
+--
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'tastypie_apiaccess', ARRAY['tastypie']),
+('public', 'tastypie_apikey', ARRAY['tastypie']);
+--
 -- Check the schema of installation for schedoc
 --
 DO
@@ -248,3 +485,5 @@ END IF;
 
 END;
 $check_start$;
+--
+--
diff --git a/dist/schedoc.sql b/dist/schedoc.sql
index ff3bf01..40b8029 100644
--- a/dist/schedoc.sql
+++ b/dist/schedoc.sql
@@ -48,16 +48,129 @@ CREATE TABLE @extschema@.schedoc_column_log (
 --
 --
 --
+CREATE TABLE @extschema@.schedoc_table_exclusion (
+  schema_name name,
+  table_name name,
+  tag text,
+  created_at timestamp with time zone DEFAULT current_timestamp,
+  created_by text DEFAULT current_user,
+  PRIMARY KEY (schema_name, table_name)
+);
 
-CREATE VIEW @extschema@.schedoc_column_comments AS
+CREATE TABLE @extschema@.schedoc_table_exclusion_templates (
+  schema_name name,
+  table_name name,
+  tags text[],
+  created_at timestamp with time zone DEFAULT current_timestamp,
+  created_by text DEFAULT current_user,
+  PRIMARY KEY (schema_name, table_name)
+);
 
-    SELECT current_database() as databasename, c.relname as tablename, a.attname as columnname, status
-    FROM schedoc_column_raw ccr
-    JOIN pg_class c ON c.oid = ccr.objoid
-    JOIN pg_attribute a ON (a.attnum = ccr.objsubid AND a.attrelid = ccr.objoid);
+--
+--
+--
+--
+-- schedoc_exclude_tool(tool text)
+-- schedoc_exclude_tools_all()
+-- schedoc_is_table_excluded(tableoid oid)
+--
+-- Set up the exclusion list
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_exclude_tool(tool text)
+RETURNS text
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  nbrows bigint;
+BEGIN
+   --
+   --
+   --
+   INSERT INTO @extschema@.schedoc_table_exclusion (schema_name, table_name, tag)
+   SELECT schema_name, table_name, tool FROM @extschema@.schedoc_table_exclusion_templates
+   WHERE tags @> ARRAY[tool];
+
+   SELECT count(1) FROM @extschema@.schedoc_table_exclusion WHERE tag = tool INTO nbrows;
+
+   RETURN format ('Inserted %s row(s) in schedoc_table_exclusion', nbrows);
+END;
+$EOF$;
+--
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_exclude_tools_all()
+RETURNS text
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  nbrows bigint;
+BEGIN
+   --
+   --
+   --
+   INSERT INTO @extschema@.schedoc_table_exclusion (schema_name, table_name, tag)
+   SELECT schema_name, table_name, tags[0] FROM @extschema@.schedoc_table_exclusion_templates;
 
+   SELECT count(1) FROM @extschema@.schedoc_table_exclusion INTO nbrows;
+
+   RETURN format ('Inserted %s row(s) in schedoc_table_exclusion', nbrows);
+END;
+$EOF$;
+--
+-- Check if a table is present in the exclusion list
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_is_table_excluded(tableoid oid)
+RETURNS boolean
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  status boolean;
+BEGIN
+    WITH
+    excluded AS (
+      SELECT c.oid
+      FROM pg_class c
+      JOIN @extschema@.schedoc_table_exclusion ste ON ste.table_name = c.relname
+      JOIN pg_namespace n ON (n.oid = c.relnamespace AND n.nspname = ste.schema_name)
+    ),
+    internals AS (
+      SELECT oid FROM excluded
+      UNION
+      SELECT c.oid FROM pg_class c
+      JOIN pg_namespace n ON (n.oid = c.relnamespace)
+      WHERE relname IN (
+            'ddl_history',
+            'ddl_history_column',
+            'ddl_history_schema',
+            'schedoc_column_log',
+            'schedoc_column_raw',
+            'schedoc_table_exclusion',
+            'schedoc_table_exclusion_templates',
+            'schedoc_valid',
+            'schedoc_valid_status')
+            AND n.nspname = '@extschema@'
+     )
+     SELECT count(1) > 0 FROM internals WHERE oid = tableoid INTO status;
+
+     RETURN status;
+END;
+$EOF$;
+--
 --
 --
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_init_existing_comments()
+RETURNS void
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  status boolean;
+BEGIN
+
+    PERFORM @extschema@.schedoc_fill_raw(objoid, objsubid)
+    FROM @extschema@.schedoc_column_existing_comments
+    WHERE description IS NOT NULL;
+
+END;
+$EOF$;
 --
 --
 --
@@ -69,47 +182,13 @@ BEGIN
    --
    -- Function to manage INSERT statements
    --
+   -- This function is called by a trigger on ddl_history
    CREATE OR REPLACE FUNCTION @extschema@.schedoc_trg()
         RETURNS trigger LANGUAGE plpgsql AS $fsub$
     BEGIN
 
-    -- keep a log of all values
-    INSERT INTO @extschema@.schedoc_column_log (objoid, objsubid, comment, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid),
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    );
-
+    PERFORM @extschema@.schedoc_fill_raw(NEW.objoid, NEW.objsubid);
 
-   -- if the json is valid
-   IF schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON THEN
-    INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, comment, status, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid)::jsonb,
-      @extschema@.schedoc_get_column_status(NEW.objoid, NEW.objsubid)::@extschema@.schedoc_status,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    ) ON CONFLICT (objoid, objsubid)
-    DO UPDATE SET
-      comment = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid)::jsonb,
-      status = @extschema@.schedoc_get_column_status(EXCLUDED.objoid, EXCLUDED.objsubid)::@extschema@.schedoc_status,
-      is_valid = @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON;
-    ELSE
-    --
-    -- This is not a valid json, we store it
-    --
-    INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    ) ON CONFLICT (objoid, objsubid)
-    DO UPDATE SET
-      is_valid = @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON;
-    END IF;
     RETURN NEW;
     END;
     $fsub$;
@@ -123,6 +202,7 @@ BEGIN
     BEGIN
     --
     --
+    IF NOT @extschema@.schedoc_is_table_excluded(NEW.attrelid) THEN
     INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
     VALUES (
       NEW.attrelid,
@@ -131,7 +211,7 @@ BEGIN
     ) ON CONFLICT (objoid, objsubid)
     DO UPDATE SET
       is_valid = false;
-
+    END IF;
     RETURN NEW;
     END;
     $fsub$;
@@ -157,6 +237,58 @@ BEGIN
 
 END;
 $EOF$;
+--
+-- schedoc_fill_raw
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_fill_raw(p_oid oid, p_subid oid)
+RETURNS void
+    LANGUAGE plpgsql AS
+$EOF$
+BEGIN
+    --
+    --
+    -- keep a log of all values
+    INSERT INTO @extschema@.schedoc_column_log (objoid, objsubid, comment, is_valid)
+    VALUES (
+        p_oid,
+        p_subid,
+        @extschema@.schedoc_get_column_description(p_oid, p_subid),
+        @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+    );
+
+    IF NOT @extschema@.schedoc_is_table_excluded(p_oid) THEN
+       -- if the json is valid
+       IF schedoc_get_column_description(p_oid, p_subid) IS JSON THEN
+          INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, comment, status, is_valid)
+          VALUES (
+             p_oid,
+             p_subid,
+             @extschema@.schedoc_get_column_description(p_oid, p_subid)::jsonb,
+             @extschema@.schedoc_get_column_status(p_oid, p_subid)::@extschema@.schedoc_status,
+             @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+          ) ON CONFLICT (objoid, objsubid)
+          DO UPDATE SET
+             comment = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid)::jsonb,
+             status = @extschema@.schedoc_get_column_status(EXCLUDED.objoid, EXCLUDED.objsubid)::@extschema@.schedoc_status,
+             is_valid = @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON;
+       ELSE
+           --
+           -- This is not a valid json, we store it
+           --
+           INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
+           VALUES (
+               p_oid,
+               p_subid,
+               @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+           ) ON CONFLICT (objoid, objsubid)
+           DO UPDATE SET
+               is_valid = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid) IS JSON;
+       END IF;
+    END IF;
+END;
+$EOF$;
+
+
 
 --
 --
@@ -232,6 +364,111 @@ BEGIN
 END;
 $EOF$;
 --
+--
+--
+
+CREATE VIEW schedoc_column_comments AS
+
+    SELECT current_database() as databasename, c.relname as tablename, a.attname as columnname, status
+    FROM schedoc_column_raw ccr
+    JOIN pg_class c ON c.oid = ccr.objoid
+    JOIN pg_attribute a ON (a.attnum = ccr.objsubid AND a.attrelid = ccr.objoid);
+--
+--
+--
+CREATE OR REPLACE VIEW schedoc_object_tables AS
+
+    SELECT n.nspname, c.relname
+    FROM pg_depend d
+    JOIN pg_class c ON c.oid = d.objid
+    JOIN pg_namespace n ON n.oid = c.relnamespace
+    JOIN pg_extension e ON e.oid = d.refobjid
+    WHERE e.extname in ('schedoc', 'ddl_historization')
+    AND c.relkind = 'r';
+--
+--
+--
+DROP VIEW IF EXISTS schedoc_column_existing_comments;
+CREATE OR REPLACE VIEW schedoc_column_existing_comments AS
+
+    WITH descr AS (
+      SELECT c.oid as objoid, d.objsubid, c.relname, d.description
+      FROM pg_class c
+      JOIN pg_namespace n ON n.oid = c.relnamespace
+      LEFT JOIN pg_description d ON d.objoid = c.oid
+      LEFT JOIN schedoc_table_exclusion e ON  e.table_name = c.relname
+      WHERE c.relkind = 'r' AND n.nspname='public'
+      AND  e.table_name IS NULL
+      AND c.relname NOT IN (
+            SELECT relname FROM @extschema@.schedoc_object_tables)
+    )
+    SELECT objoid, objsubid, relname, description, description IS NOT NULL AND  description IS JSON as is_ok
+    FROM descr
+
+ORDER BY relname
+;
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'celery_results_taskresult', ARRAY['celery']),
+('public', 'celery_taskmeta', ARRAY['celery']),
+('public', 'celery_tasksetmeta', ARRAY['celery']),
+
+('public', 'djcelery_crontabschedule', ARRAY['celery']),
+('public', 'djcelery_intervalschedule', ARRAY['celery']),
+('public', 'djcelery_periodictask', ARRAY['celery']),
+('public', 'djcelery_taskstate', ARRAY['celery']),
+('public', 'djcelery_workerstate', ARRAY['celery']);
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'dbz_signal', ARRAY['debezium']),
+('public', 'dbz_heartbeat', ARRAY['debezium']);
+--
+-- Exclude tables created by Django Framework
+--
+-- https://www.djangoproject.com/
+--
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+('public', 'auth_group', ARRAY['django']),
+('public', 'auth_group_permissions', ARRAY['django']),
+('public', 'auth_permission', ARRAY['django']),
+('public', 'auth_user', ARRAY['django']),
+('public', 'auth_user_groups', ARRAY['django']),
+('public', 'auth_user_user_permissions', ARRAY['django']),
+('public', 'django_admin_log', ARRAY['django']),
+('public', 'django_content_type', ARRAY['django']),
+('public', 'django_migrations', ARRAY['django']),
+('public', 'django_session', ARRAY['django']);
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'procrastinate_events', ARRAY['procrastinate']),
+('public', 'procrastinate_jobs', ARRAY['procrastinate']),
+('public', 'procrastinate_periodic_defers', ARRAY['procrastinate']);
+--
+--
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'tastypie_apiaccess', ARRAY['tastypie']),
+('public', 'tastypie_apikey', ARRAY['tastypie']);
+--
 -- Check the schema of installation for schedoc
 --
 DO
@@ -248,3 +485,5 @@ END IF;
 
 END;
 $check_start$;
+--
+--
diff --git a/sql/function.sql b/sql/function.sql
index c9a7628..ca389cd 100644
--- a/sql/function.sql
+++ b/sql/function.sql
@@ -9,47 +9,13 @@ BEGIN
    --
    -- Function to manage INSERT statements
    --
+   -- This function is called by a trigger on ddl_history
    CREATE OR REPLACE FUNCTION @extschema@.schedoc_trg()
         RETURNS trigger LANGUAGE plpgsql AS $fsub$
     BEGIN
 
-    -- keep a log of all values
-    INSERT INTO @extschema@.schedoc_column_log (objoid, objsubid, comment, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid),
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    );
-
+    PERFORM @extschema@.schedoc_fill_raw(NEW.objoid, NEW.objsubid);
 
-   -- if the json is valid
-   IF schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON THEN
-    INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, comment, status, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid)::jsonb,
-      @extschema@.schedoc_get_column_status(NEW.objoid, NEW.objsubid)::@extschema@.schedoc_status,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    ) ON CONFLICT (objoid, objsubid)
-    DO UPDATE SET
-      comment = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid)::jsonb,
-      status = @extschema@.schedoc_get_column_status(EXCLUDED.objoid, EXCLUDED.objsubid)::@extschema@.schedoc_status,
-      is_valid = @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON;
-    ELSE
-    --
-    -- This is not a valid json, we store it
-    --
-    INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
-    VALUES (
-      NEW.objoid,
-      NEW.objsubid,
-      @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON
-    ) ON CONFLICT (objoid, objsubid)
-    DO UPDATE SET
-      is_valid = @extschema@.schedoc_get_column_description(NEW.objoid, NEW.objsubid) IS JSON;
-    END IF;
     RETURN NEW;
     END;
     $fsub$;
@@ -63,6 +29,7 @@ BEGIN
     BEGIN
     --
     --
+    IF NOT @extschema@.schedoc_is_table_excluded(NEW.attrelid) THEN
     INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
     VALUES (
       NEW.attrelid,
@@ -71,7 +38,7 @@ BEGIN
     ) ON CONFLICT (objoid, objsubid)
     DO UPDATE SET
       is_valid = false;
-
+    END IF;
     RETURN NEW;
     END;
     $fsub$;
@@ -97,6 +64,58 @@ BEGIN
 
 END;
 $EOF$;
+--
+-- schedoc_fill_raw
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_fill_raw(p_oid oid, p_subid oid)
+RETURNS void
+    LANGUAGE plpgsql AS
+$EOF$
+BEGIN
+    --
+    --
+    -- keep a log of all values
+    INSERT INTO @extschema@.schedoc_column_log (objoid, objsubid, comment, is_valid)
+    VALUES (
+        p_oid,
+        p_subid,
+        @extschema@.schedoc_get_column_description(p_oid, p_subid),
+        @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+    );
+
+    IF NOT @extschema@.schedoc_is_table_excluded(p_oid) THEN
+       -- if the json is valid
+       IF schedoc_get_column_description(p_oid, p_subid) IS JSON THEN
+          INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, comment, status, is_valid)
+          VALUES (
+             p_oid,
+             p_subid,
+             @extschema@.schedoc_get_column_description(p_oid, p_subid)::jsonb,
+             @extschema@.schedoc_get_column_status(p_oid, p_subid)::@extschema@.schedoc_status,
+             @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+          ) ON CONFLICT (objoid, objsubid)
+          DO UPDATE SET
+             comment = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid)::jsonb,
+             status = @extschema@.schedoc_get_column_status(EXCLUDED.objoid, EXCLUDED.objsubid)::@extschema@.schedoc_status,
+             is_valid = @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON;
+       ELSE
+           --
+           -- This is not a valid json, we store it
+           --
+           INSERT INTO @extschema@.schedoc_column_raw (objoid, objsubid, is_valid)
+           VALUES (
+               p_oid,
+               p_subid,
+               @extschema@.schedoc_get_column_description(p_oid, p_subid) IS JSON
+           ) ON CONFLICT (objoid, objsubid)
+           DO UPDATE SET
+               is_valid = @extschema@.schedoc_get_column_description(EXCLUDED.objoid, EXCLUDED.objsubid) IS JSON;
+       END IF;
+    END IF;
+END;
+$EOF$;
+
+
 
 --
 --
diff --git a/sql/management.sql b/sql/management.sql
new file mode 100644
index 0000000..617f682
--- /dev/null
+++ b/sql/management.sql
@@ -0,0 +1,102 @@
+--
+-- schedoc_exclude_tool(tool text)
+-- schedoc_exclude_tools_all()
+-- schedoc_is_table_excluded(tableoid oid)
+--
+-- Set up the exclusion list
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_exclude_tool(tool text)
+RETURNS text
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  nbrows bigint;
+BEGIN
+   --
+   --
+   --
+   INSERT INTO @extschema@.schedoc_table_exclusion (schema_name, table_name, tag)
+   SELECT schema_name, table_name, tool FROM @extschema@.schedoc_table_exclusion_templates
+   WHERE tags @> ARRAY[tool];
+
+   SELECT count(1) FROM @extschema@.schedoc_table_exclusion WHERE tag = tool INTO nbrows;
+
+   RETURN format ('Inserted %s row(s) in schedoc_table_exclusion', nbrows);
+END;
+$EOF$;
+--
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_exclude_tools_all()
+RETURNS text
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  nbrows bigint;
+BEGIN
+   --
+   --
+   --
+   INSERT INTO @extschema@.schedoc_table_exclusion (schema_name, table_name, tag)
+   SELECT schema_name, table_name, tags[0] FROM @extschema@.schedoc_table_exclusion_templates;
+
+   SELECT count(1) FROM @extschema@.schedoc_table_exclusion INTO nbrows;
+
+   RETURN format ('Inserted %s row(s) in schedoc_table_exclusion', nbrows);
+END;
+$EOF$;
+--
+-- Check if a table is present in the exclusion list
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_is_table_excluded(tableoid oid)
+RETURNS boolean
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  status boolean;
+BEGIN
+    WITH
+    excluded AS (
+      SELECT c.oid
+      FROM pg_class c
+      JOIN @extschema@.schedoc_table_exclusion ste ON ste.table_name = c.relname
+      JOIN pg_namespace n ON (n.oid = c.relnamespace AND n.nspname = ste.schema_name)
+    ),
+    internals AS (
+      SELECT oid FROM excluded
+      UNION
+      SELECT c.oid FROM pg_class c
+      JOIN pg_namespace n ON (n.oid = c.relnamespace)
+      WHERE relname IN (
+            'ddl_history',
+            'ddl_history_column',
+            'ddl_history_schema',
+            'schedoc_column_log',
+            'schedoc_column_raw',
+            'schedoc_table_exclusion',
+            'schedoc_table_exclusion_templates',
+            'schedoc_valid',
+            'schedoc_valid_status')
+            AND n.nspname = '@extschema@'
+     )
+     SELECT count(1) > 0 FROM internals WHERE oid = tableoid INTO status;
+
+     RETURN status;
+END;
+$EOF$;
+--
+--
+--
+CREATE OR REPLACE FUNCTION @extschema@.schedoc_init_existing_comments()
+RETURNS void
+LANGUAGE plpgsql AS
+$EOF$
+DECLARE
+  status boolean;
+BEGIN
+
+    PERFORM @extschema@.schedoc_fill_raw(objoid, objsubid)
+    FROM @extschema@.schedoc_column_existing_comments
+    WHERE description IS NOT NULL;
+
+END;
+$EOF$;
diff --git a/sql/start.sql b/sql/start.sql
index 26fe3a1..8c20bf5 100644
--- a/sql/start.sql
+++ b/sql/start.sql
@@ -15,3 +15,5 @@ END IF;
 
 END;
 $check_start$;
+--
+--
diff --git a/sql/table.sql b/sql/table.sql
index 3f67469..c855678 100644
--- a/sql/table.sql
+++ b/sql/table.sql
@@ -48,13 +48,24 @@ CREATE TABLE @extschema@.schedoc_column_log (
 --
 --
 --
+CREATE TABLE @extschema@.schedoc_table_exclusion (
+  schema_name name,
+  table_name name,
+  tag text,
+  created_at timestamp with time zone DEFAULT current_timestamp,
+  created_by text DEFAULT current_user,
+  PRIMARY KEY (schema_name, table_name)
+);
 
-CREATE VIEW @extschema@.schedoc_column_comments AS
-
-    SELECT current_database() as databasename, c.relname as tablename, a.attname as columnname, status
-    FROM schedoc_column_raw ccr
-    JOIN pg_class c ON c.oid = ccr.objoid
-    JOIN pg_attribute a ON (a.attnum = ccr.objsubid AND a.attrelid = ccr.objoid);
+CREATE TABLE @extschema@.schedoc_table_exclusion_templates (
+  schema_name name,
+  table_name name,
+  tags text[],
+  created_at timestamp with time zone DEFAULT current_timestamp,
+  created_by text DEFAULT current_user,
+  PRIMARY KEY (schema_name, table_name)
+);
 
 --
 --
+--
diff --git a/sql/view.sql b/sql/view.sql
new file mode 100644
index 0000000..7d18987
--- /dev/null
+++ b/sql/view.sql
@@ -0,0 +1,44 @@
+--
+--
+--
+
+CREATE VIEW schedoc_column_comments AS
+
+    SELECT current_database() as databasename, c.relname as tablename, a.attname as columnname, status
+    FROM schedoc_column_raw ccr
+    JOIN pg_class c ON c.oid = ccr.objoid
+    JOIN pg_attribute a ON (a.attnum = ccr.objsubid AND a.attrelid = ccr.objoid);
+--
+--
+--
+CREATE OR REPLACE VIEW schedoc_object_tables AS
+
+    SELECT n.nspname, c.relname
+    FROM pg_depend d
+    JOIN pg_class c ON c.oid = d.objid
+    JOIN pg_namespace n ON n.oid = c.relnamespace
+    JOIN pg_extension e ON e.oid = d.refobjid
+    WHERE e.extname in ('schedoc', 'ddl_historization')
+    AND c.relkind = 'r';
+--
+--
+--
+DROP VIEW IF EXISTS schedoc_column_existing_comments;
+CREATE OR REPLACE VIEW schedoc_column_existing_comments AS
+
+    WITH descr AS (
+      SELECT c.oid as objoid, d.objsubid, c.relname, d.description
+      FROM pg_class c
+      JOIN pg_namespace n ON n.oid = c.relnamespace
+      LEFT JOIN pg_description d ON d.objoid = c.oid
+      LEFT JOIN schedoc_table_exclusion e ON  e.table_name = c.relname
+      WHERE c.relkind = 'r' AND n.nspname='public'
+      AND  e.table_name IS NULL
+      AND c.relname NOT IN (
+            SELECT relname FROM @extschema@.schedoc_object_tables)
+    )
+    SELECT objoid, objsubid, relname, description, description IS NOT NULL AND  description IS JSON as is_ok
+    FROM descr
+
+ORDER BY relname
+;
diff --git a/test/create_table.sql.in b/test/create_table.sql.in
index b03c07f..a1186eb 100644
--- a/test/create_table.sql.in
+++ b/test/create_table.sql.in
@@ -1,7 +1,5 @@
 --
 --
---
-
 SET search_path=public,pgtap,_TEST_SCHEMA_;
 
 BEGIN;
diff --git a/test/sql/function_test.sql.in b/test/sql/function_test.sql.in
index 7f927da..77dfa97 100644
--- a/test/sql/function_test.sql.in
+++ b/test/sql/function_test.sql.in
@@ -6,11 +6,12 @@ SET search_path=public,pgtap;
 
 BEGIN;
 
-SELECT plan(4);
+SELECT plan(5);
 
 SELECT has_extension('schedoc');
 
 SELECT has_function('_TEST_SCHEMA_'::name, 'schedoc_start'::name);
+SELECT has_function('_TEST_SCHEMA_'::name, 'schedoc_fill_raw'::name);
 SELECT has_function('_TEST_SCHEMA_'::name, 'schedoc_get_column_description'::name, ARRAY['oid', 'oid']);
 SELECT has_function('_TEST_SCHEMA_'::name, 'schedoc_get_column_status'::name, ARRAY['oid', 'oid']);
 
diff --git a/test/sql/management_test.sql.in b/test/sql/management_test.sql.in
new file mode 100644
index 0000000..a7618ca
--- /dev/null
+++ b/test/sql/management_test.sql.in
@@ -0,0 +1,71 @@
+--
+--
+--
+SET search_path=public,pgtap,_TEST_SCHEMA_;
+
+BEGIN;
+
+SELECT plan(14);
+
+SELECT has_function('_TEST_SCHEMA_'::name, 'schedoc_exclude_tool'::name, ARRAY['text']);
+SELECT has_function('_TEST_SCHEMA_'::name, 'schedoc_exclude_tools_all'::name);
+SELECT has_function('_TEST_SCHEMA_'::name, 'schedoc_is_table_excluded'::name, ARRAY['oid']);
+SELECT has_function('_TEST_SCHEMA_'::name, 'schedoc_init_existing_comments'::name);
+--
+-- Return False on non existing id
+--
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(0)',
+    ARRAY['False'::boolean],
+    'Return False on non existing id');
+
+
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''ddl_history''',
+    ARRAY['True'::boolean],
+    'The table ddl_history is excluded');
+
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''ddl_history_column''',
+    ARRAY['True'::boolean],
+    'The table ddl_history_column is excluded');
+
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''ddl_history_schema''',
+    ARRAY['True'::boolean],
+    'The table ddl_history_schema is excluded');
+
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''schedoc_column_log''',
+    ARRAY['True'::boolean],
+    'The table schedoc_column_log is excluded');
+
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''schedoc_column_raw''',
+    ARRAY['True'::boolean],
+    'The table schedoc_column_raw is excluded');
+
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''schedoc_table_exclusion''',
+    ARRAY['True'::boolean],
+    'The table schedoc_table_exclusion is excluded');
+
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''schedoc_table_exclusion_templates''',
+    ARRAY['True'::boolean],
+    'The table schedoc_table_exclusion_templates is excluded');
+
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''schedoc_valid''',
+    ARRAY['True'::boolean],
+    'The table schedoc_valid is excluded');
+
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''schedoc_valid_status''',
+    ARRAY['True'::boolean],
+    'The table schedoc_valid_status is excluded');
+
+SELECT finish();
+
+
+ROLLBACK;
diff --git a/test/sql/table_test.sql.in b/test/sql/table_test.sql.in
index d52ccdf..9125ff0 100644
--- a/test/sql/table_test.sql.in
+++ b/test/sql/table_test.sql.in
@@ -1,19 +1,28 @@
 --
--- We assume that ddl_historization is installed in public schema
 --
-
+--
 SET search_path=public,pgtap;
 
 BEGIN;
 
-SELECT plan(5);
+SELECT plan(8);
 
-SELECT has_extension('schedoc');
 SELECT has_table('_TEST_SCHEMA_'::name, 'schedoc_column_raw'::name);
-SELECT has_view('_TEST_SCHEMA_'::name, 'schedoc_column_comments'::name);
+
+SELECT has_table('_TEST_SCHEMA_'::name, 'schedoc_valid'::name);
+
+SELECT has_table('_TEST_SCHEMA_'::name, 'schedoc_valid_status'::name);
+
+SELECT has_table('_TEST_SCHEMA_'::name, 'schedoc_column_log'::name);
+
+SELECT has_table('_TEST_SCHEMA_'::name, 'schedoc_table_exclusion'::name);
+
+SELECT has_table('_TEST_SCHEMA_'::name, 'schedoc_table_exclusion_templates'::name);
 
 SELECT has_enum('_TEST_SCHEMA_'::name, 'schedoc_status'::name);
 
 SELECT enum_has_labels('_TEST_SCHEMA_'::name, 'schedoc_status'::name, ARRAY['public', 'private', 'legacy', 'wip']);
 
+SELECT finish();
+
 ROLLBACK;
diff --git a/test/sql/view_test.sql.in b/test/sql/view_test.sql.in
new file mode 100644
index 0000000..e81d90a
--- /dev/null
+++ b/test/sql/view_test.sql.in
@@ -0,0 +1,16 @@
+--
+-- 2 views
+--
+SET search_path=public,_TEST_SCHEMA_;
+
+BEGIN;
+
+SELECT plan(2);
+
+SELECT has_view('_TEST_SCHEMA_'::name, 'schedoc_column_existing_comments'::name);
+
+SELECT has_view('_TEST_SCHEMA_'::name, 'schedoc_column_comments'::name);
+
+SELECT finish();
+
+ROLLBACK;
diff --git a/test/table_exclusion.sql.in b/test/table_exclusion.sql.in
new file mode 100644
index 0000000..84c798b
--- /dev/null
+++ b/test/table_exclusion.sql.in
@@ -0,0 +1,69 @@
+--
+-- We assume that ddl_historization is installed in public schema
+--
+
+SET search_path=public,pgtap,_TEST_SCHEMA_;
+
+BEGIN;
+
+SELECT plan(7);
+
+DROP EXTENSION IF EXISTS schedoc CASCADE;
+CREATE EXTENSION schedoc WITH SCHEMA _TEST_SCHEMA_ CASCADE;
+SELECT schedoc_start();
+
+TRUNCATE schedoc_column_raw;
+TRUNCATE schedoc_column_log;
+TRUNCATE ddl_history;
+
+-- create the table before the exclusion list is loaded
+CREATE TABLE IF NOT EXISTS dbz_signal (id int);
+
+SELECT results_eq(
+    'SELECT count(*) FROM schedoc_column_raw',
+    'SELECT CAST(1 as bigint)',
+    'We have 1 row in schedoc_column_raw');
+
+SELECT results_eq(
+    'SELECT count(*) FROM schedoc_column_log',
+    'SELECT CAST(0 as bigint)',
+    'We have 0 row in schedoc_column_log');
+
+
+-- the table is not excluded by default
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''dbz_signal''',
+    ARRAY['False'::boolean],
+    'The table dbz_signal is not excluded');
+
+-- load the exclusion list
+SELECT schedoc_exclude_tool('debezium');
+
+SELECT results_eq(
+    'SELECT count(*) FROM schedoc_table_exclusion',
+    'SELECT CAST(2 as bigint)',
+    'We have 2 rows in schedoc_table_exclusion');
+
+-- create a table after the exclusion list is loaded
+CREATE TABLE IF NOT EXISTS dbz_heartbeat (id int);
+
+-- Now the table is excluded
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''dbz_signal''',
+    ARRAY['True'::boolean],
+    'The table dbz_signal is excluded');
+
+SELECT results_eq(
+    'SELECT schedoc_is_table_excluded(oid) FROM pg_class WHERE relname=''dbz_heartbeat''',
+    ARRAY['True'::boolean],
+    'The table dbz_hearbeat is excluded');
+
+-- There is only the column id of table dbz_signal
+SELECT results_eq(
+    'SELECT count(*) FROM schedoc_column_raw',
+    'SELECT CAST(1 as bigint)',
+    'We have 1 row in schedoc_column_raw');
+
+SELECT finish();
+
+ROLLBACK;
diff --git a/tools_exclusion/celery.sql b/tools_exclusion/celery.sql
new file mode 100644
index 0000000..f59023f
--- /dev/null
+++ b/tools_exclusion/celery.sql
@@ -0,0 +1,16 @@
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'celery_results_taskresult', ARRAY['celery']),
+('public', 'celery_taskmeta', ARRAY['celery']),
+('public', 'celery_tasksetmeta', ARRAY['celery']),
+
+('public', 'djcelery_crontabschedule', ARRAY['celery']),
+('public', 'djcelery_intervalschedule', ARRAY['celery']),
+('public', 'djcelery_periodictask', ARRAY['celery']),
+('public', 'djcelery_taskstate', ARRAY['celery']),
+('public', 'djcelery_workerstate', ARRAY['celery']);
diff --git a/tools_exclusion/debezium.sql b/tools_exclusion/debezium.sql
new file mode 100644
index 0000000..2356e8e
--- /dev/null
+++ b/tools_exclusion/debezium.sql
@@ -0,0 +1,9 @@
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'dbz_signal', ARRAY['debezium']),
+('public', 'dbz_heartbeat', ARRAY['debezium']);
diff --git a/tools_exclusion/django.sql b/tools_exclusion/django.sql
new file mode 100644
index 0000000..ebc5191
--- /dev/null
+++ b/tools_exclusion/django.sql
@@ -0,0 +1,17 @@
+--
+-- Exclude tables created by Django Framework
+--
+-- https://www.djangoproject.com/
+--
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+('public', 'auth_group', ARRAY['django']),
+('public', 'auth_group_permissions', ARRAY['django']),
+('public', 'auth_permission', ARRAY['django']),
+('public', 'auth_user', ARRAY['django']),
+('public', 'auth_user_groups', ARRAY['django']),
+('public', 'auth_user_user_permissions', ARRAY['django']),
+('public', 'django_admin_log', ARRAY['django']),
+('public', 'django_content_type', ARRAY['django']),
+('public', 'django_migrations', ARRAY['django']),
+('public', 'django_session', ARRAY['django']);
diff --git a/tools_exclusion/procrastinate.sql b/tools_exclusion/procrastinate.sql
new file mode 100644
index 0000000..25ce607
--- /dev/null
+++ b/tools_exclusion/procrastinate.sql
@@ -0,0 +1,10 @@
+--
+-- Debezium
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'procrastinate_events', ARRAY['procrastinate']),
+('public', 'procrastinate_jobs', ARRAY['procrastinate']),
+('public', 'procrastinate_periodic_defers', ARRAY['procrastinate']);
diff --git a/tools_exclusion/tastypie.sql b/tools_exclusion/tastypie.sql
new file mode 100644
index 0000000..c3c56a1
--- /dev/null
+++ b/tools_exclusion/tastypie.sql
@@ -0,0 +1,9 @@
+--
+--
+--
+
+INSERT INTO @extschema@.schedoc_table_exclusion_templates (schema_name, table_name, tags)
+VALUES
+
+('public', 'tastypie_apiaccess', ARRAY['tastypie']),
+('public', 'tastypie_apikey', ARRAY['tastypie']);