From 8bbe63fee713a9d8112e62409a840139e665472b Mon Sep 17 00:00:00 2001
From: Maciej Ziarkowski <maciej.ziarkowski@gmail.com>
Date: Mon, 2 Dec 2019 20:58:50 +0000
Subject: [PATCH] Add land use groups lookup, drop original land use

---
 migrations/0xx.landuse.down.sql |  3 ++
 migrations/0xx.landuse.up.sql   | 75 +++++++++++++++++----------------
 2 files changed, 41 insertions(+), 37 deletions(-)

diff --git a/migrations/0xx.landuse.down.sql b/migrations/0xx.landuse.down.sql
index c183bc13..f7bc3f0b 100644
--- a/migrations/0xx.landuse.down.sql
+++ b/migrations/0xx.landuse.down.sql
@@ -3,11 +3,14 @@
 --Landuse is a table as #358
 --Land use class, group and order will be stored in a new table
 DROP TABLE IF EXISTS reference_tables.buildings_landuse_order CASCADE;
+DROP TABLE IF EXISTS reference_tables.buildings_landuse_group CASCADE;
 DROP TABLE IF EXISTS reference_tables.buildings_landuse_class CASCADE;
 
 -- Land use class or classes, array object, client constrained.
 ALTER TABLE buildings DROP COLUMN IF EXISTS current_landuse_class;
 
+ALTER TABLE buildings DROP COLUMN IF EXISTS current_landuse_group;
+
 -- Land use order, singular. Client and db constrained.
 ALTER TABLE buildings DROP COLUMN IF EXISTS current_landuse_order;
 
diff --git a/migrations/0xx.landuse.up.sql b/migrations/0xx.landuse.up.sql
index 9f3ae1ee..f182f9b6 100644
--- a/migrations/0xx.landuse.up.sql
+++ b/migrations/0xx.landuse.up.sql
@@ -6,52 +6,53 @@
 
 CREATE TABLE IF NOT EXISTS reference_tables.buildings_landuse_order AS
 SELECT a.landuse_id,
-       a.description,
-       a."level",
-       a.parent_id,
-       a.parent_name
+       a.description
 FROM reference_tables.landuse_classifications a
-WHERE a."level" = 'order'
-  AND a.is_used IS TRUE ;
+WHERE a.level = 'order'
+  AND a.is_used;
+
+ALTER TABLE reference_tables.buildings_landuse_order
+ADD UNIQUE (description);
+
+
+CREATE TABLE IF NOT EXISTS reference_tables.buildings_landuse_group AS
+SELECT a.landuse_id,
+       a.description,
+       a.parent_id AS parent_order_id
+FROM reference_tables.landuse_classifications a
+WHERE a.level = 'group'
+  AND a.is_used;
+
+ALTER TABLE reference_tables.buildings_landuse_group
+ADD UNIQUE (description);
+
 
 --the below is for front end reference, not current used as a constraint
-  CREATE TABLE IF NOT EXISTS reference_tables.buildings_landuse_class AS
-  SELECT a.landuse_id,
-         a.description,
-         a."level",
-         a.parent_id,
-         a.parent_name
-  FROM reference_tables.landuse_classifications a
-  WHERE a."level" = 'class'
-    AND a.is_used IS TRUE ;
-
-ALTER TABLE buildings ADD COLUMN IF NOT EXISTS current_landuse_order text, ADD CONSTRAINT fk_current_landuse_order
-FOREIGN KEY (current_landuse_order) REFERENCES reference_tables.buildings_landuse_order (description);
+CREATE TABLE IF NOT EXISTS reference_tables.buildings_landuse_class AS
+SELECT a.landuse_id,
+       a.description,
+       a.parent_id AS parent_group_id
+FROM reference_tables.landuse_classifications a
+WHERE a.level = 'class'
+  AND a.is_used;
 
 --Landuse is hierachical. Highest level is Order (Residential) then Group (Residential-Dwelling) then Class (Residential-Dwelling-Detached house)
 --Interface will collected most detailed (class) but visualise highest level (order)
 --Landuse is a table as #358
 --Prerequisite run bulk_sources migration first
  -- Land use is table with 3 levels of hierachy (highest to lowest). order > group > class
+
+
+-- Land use order, singular. Client and db constrained with foreign key
+ALTER TABLE buildings
+  ADD COLUMN IF NOT EXISTS current_landuse_order text,
+  ADD FOREIGN KEY (current_landuse_order)
+  REFERENCES reference_tables.buildings_landuse_order (description);
+
+
+-- Land use groups, array. Derived from classes.
+ALTER TABLE buildings ADD COLUMN IF NOT EXISTS current_landuse_group text ARRAY[41];
+
  -- Land use class or classes, array object, client constrained. ARRAY[] is used to constrain array size. The array is limited to 250 based on Westfield Stratford as a single toid with many uses, this may want to be reduced down to reduce maximum size.
 
 ALTER TABLE buildings ADD COLUMN IF NOT EXISTS current_landuse_class text ARRAY[250];
-
--- Land use order, singular. Client and db constrained with foreign key
-
-
-
---===========================================
---
--- We also collect original landuse, structure & process is as current land use
--- We don't currently collect intermediate historic uses
---
---===========================================
- -- Original Land use class or classes, array object, client constrained.
-
-ALTER TABLE buildings ADD COLUMN IF NOT EXISTS original_landuse_class text ARRAY[250];
-
--- Land use order, singular. Client and db constrained.
-
-ALTER TABLE buildings ADD COLUMN IF NOT EXISTS original_landuse_order text, ADD CONSTRAINT fk_original_landuse_order
-FOREIGN KEY (original_landuse_order) REFERENCES reference_tables.buildings_landuse_order (description);