diff --git a/cdviz-db/examples/queries.sql b/cdviz-db/examples/queries.sql
new file mode 100644
index 0000000..8f0ee71
--- /dev/null
+++ b/cdviz-db/examples/queries.sql
@@ -0,0 +1,69 @@
+-- find all subject
+SELECT DISTINCT "subject" FROM "cdevents_lake";
+
+-- find all predicate for a subject
+SELECT DISTINCT "predicate" FROM "cdevents_lake" WHERE subject IN ($subjects)
+
+-- 
+select payload -> 'subject' -> 'content' -> 'artifactId' as artifact from cdevents_lake
+where subject = 'service'
+and  predicate = 'deployed'
+-- and payload -> 'subject' -> 'content' -> 'environment' ->> 'id' IN ('%')
+-- and payload -> 'subject' -> 'content' ->> 'artfactId' IN ('%')
+;
+
+-- 'pkg:oci/myapp@sha256%3A0b31b1c02ff458ad9b7b81cbdf8f028bd54699fa151f221d1e8de6817db93427'
+select alias, description, token from ts_debug('pkg:oci/myapp@sha256%3A0b31b1c02ff458ad9b7b81cbdf8f028bd54699fa151f221d1e8de6817db93427')
+;
+
+select regexp_match (
+ 'pkg:oci/myapp@sha256%3A0b31b1c02ff458ad9b7b81cbdf8f028bd54699fa151f221d1e8de6817db93427',
+  'pkg:(\w*)/(.*)@(.*)(\?.*)?(#.*)?' 
+)
+;
+
+drop function extract_purl_fields;
+DROP type purl_fields;
+
+create TYPE purl_fields AS ("type" varchar(32), "name" varchar(256) , "version" varchar(128), "qualifier" varchar(256), "subpath" varchar(256));
+
+CREATE OR REPLACE FUNCTION extract_purl_fields(purl text) 
+RETURNS purl_fields 
+AS 
+$$
+DECLARE
+  result_record public.purl_fields;
+
+BEGIN
+  select  m[1], m[2], m[3], m[4], m[5]
+  INTO result_record.type, result_record.name, result_record.version, result_record.qualifier, result_record.subpath
+  from regexp_match (purl, 'pkg:(\w*)/(.*)@(.*)(\?.*)?(#.*)?') as m
+  ;
+  RETURN result_record;
+END
+$$ LANGUAGE plpgsql;
+
+select extract_purl_fields('pkg:oci/myapp@sha256%3A0b31b1c02ff458ad9b7b81cbdf8f028bd54699fa151f221d1e8de6817db93427')
+
+select distinct a.name from cdevents_lake as c, extract_purl_fields(c.payload -> 'subject' -> 'content' ->> 'artifactId') as a;
+
+select extract_purl_fields(payload -> 'subject' -> 'content' ->> 'artifactId') as artifact from cdevents_lake
+where subject = 'service'
+and  predicate = 'deployed'
+and payload -> 'subject' -> 'content' -> 'environment' ->> 'id' similar to  '(%)'
+and payload -> 'subject' -> 'content' ->> 'artfactId' similar to '/(%)?'
+;
+
+--TODO define a procedural function to insert event (how to validate json)
+--TODO list query (natural + sql) about what we want
+-- - what is the deployed version per environment for application X at time t ?
+-- - what is the history of an application (optional filter version, environment)?
+-- - what is the status of application's version ?
+-- - what is deployed in environment (pattern) ?
+-- - how many time for a version between 2 environment?
+-- - how many time for a version between build/publish/first deploy/last deploy?
+-- order version by timestamp (on ???)
+--TODO create readonly view per subject with some extraction ?
+-- compare (explain) query over view vs query direct on lake
+--TODO create the role to view data
+--TODO create the role to push data (via the procedure call)
\ No newline at end of file
diff --git a/demos/example_01/cdevents/cdevents.csv b/demos/example_01/cdevents/cdevents.csv
new file mode 100644
index 0000000..5b1a502
--- /dev/null
+++ b/demos/example_01/cdevents/cdevents.csv
@@ -0,0 +1,6 @@
+uuid,timestamp,id,env,artifact_id
+0fe3789b-6094-4cce-bb23-c949e1c4fdf1,2024-06-20T22:11:50.926Z,1,dev,pkg:oci/myapp@sha256%3A0b31b1c02ff458ad9b7b81cbdf8f028bd54699fa151f221d1e8de6817db93427
+20222a04-71d0-4164-97b7-40a2f26d5951,2024-06-20T22:11:55.926Z,2,stg,pkg:oci/myapp@sha256%3A0b31b1c02ff458ad9b7b81cbdf8f028bd54699fa151f221d1e8de6817db93427
+5111bde6-8cf7-4961-a4f5-f5621146fa2b,2024-06-20T22:13:00.926Z,3,pro-z1,pkg:oci/myapp@sha256%3A0b31b1c02ff458ad9b7b81cbdf8f028bd54699fa151f221d1e8de6817db93427
+ed4bf81e-be01-4bf4-9a0f-98b1ade93461,2024-06-20T22:13:10.926Z,3,pro-z2,pkg:oci/myapp@sha256%3A0b31b1c02ff458ad9b7b81cbdf8f028bd54699fa151f221d1e8de6817db93427
+c5eab6d9-d9aa-482e-a785-ae581c32598b,2024-06-21T22:11:50.926Z,1,dev,pkg:oci/myapp@0.1