user table schema

db/migrations/V2025020311210__db_users_schema.sql

@@ -0,0 +1,43 @@
+-- hash combination of private id with salt to generate unique external id
+CREATE FUNCTION gu_generate_identifier_with_salt(private_uuid UUID, salt VARCHAR) RETURNS VARCHAR
+    LANGUAGE SQL
+    IMMUTABLE
+    RETURNS NULL ON NULL INPUT
+    RETURN encode(sha256((private_uuid || salt)::bytea), 'hex');
+
+CREATE FUNCTION gu_google_tag_id(private_uuid UUID) RETURNS VARCHAR
+    LANGUAGE SQL
+    IMMUTABLE
+    RETURNS NULL ON NULL INPUT
+    -- the salts are not secrets, they are used to avoid sharing the private id with third parties
+    RETURN gu_generate_identifier_with_salt(private_uuid, 'c16a3672d5404771baa2e10668cc1285');
+
+CREATE TABLE users (
+    id VARCHAR PRIMARY KEY,
+    okta_id VARCHAR UNIQUE NOT NULL,
+    username VARCHAR UNIQUE,
+    braze_uuid UUID UNIQUE NOT NULL DEFAULT gen_random_uuid(),
+    private_uuid UUID UNIQUE NOT NULL DEFAULT gen_random_uuid(),
+    google_tag_id VARCHAR UNIQUE NOT NULL
+);
+
+COMMENT ON COLUMN users.private_uuid IS 'private id used to generate external ids';
+COMMENT ON COLUMN users.google_tag_id IS 'generated by the gu_before_insert_user_tr "before insert" trigger, do not provide manually';
+
+CREATE OR REPLACE FUNCTION gu_before_insert_user_fn()
+    RETURNS TRIGGER
+    LANGUAGE PLPGSQL
+    AS
+        $$
+        BEGIN
+            NEW.google_tag_id = gu_google_tag_id(NEW.private_uuid);
+            RETURN NEW;
+        END;
+        $$;
+
+CREATE TRIGGER gu_before_insert_user_tr
+BEFORE INSERT
+ON users
+FOR EACH ROW
+EXECUTE FUNCTION gu_before_insert_user_fn();
+