Initial commit.

script/pgsnapshot_schema_0.6.sql

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+-- Database creation script for the snapshot PostgreSQL schema.
+
+-- Drop all tables if they exist.
+DROP TABLE IF EXISTS actions;
+DROP TABLE IF EXISTS users;
+DROP TABLE IF EXISTS nodes;
+DROP TABLE IF EXISTS ways;
+DROP TABLE IF EXISTS way_nodes;
+DROP TABLE IF EXISTS relations;
+DROP TABLE IF EXISTS relation_members;
+DROP TABLE IF EXISTS schema_info;
+
+-- Drop all stored procedures if they exist.
+DROP FUNCTION IF EXISTS osmosisUpdate();
+
+
+-- Create a table which will contain a single row defining the current schema version.
+CREATE TABLE schema_info (
+    version integer NOT NULL
+);
+
+
+-- Create a table for users.
+CREATE TABLE users (
+    id int NOT NULL,
+    name text NOT NULL
+);
+
+
+-- Create a table for nodes.
+CREATE TABLE nodes (
+    id bigint NOT NULL,
+    version int NOT NULL,
+    user_id int NOT NULL,
+    tstamp timestamp without time zone NOT NULL,
+    changeset_id bigint NOT NULL,
+    tags hstore
+);
+-- Add a postgis point column holding the location of the node.
+SELECT AddGeometryColumn('nodes', 'geom', 4326, 'POINT', 2);
+
+
+-- Create a table for ways.
+CREATE TABLE ways (
+    id bigint NOT NULL,
+    version int NOT NULL,
+    user_id int NOT NULL,
+    tstamp timestamp without time zone NOT NULL,
+    changeset_id bigint NOT NULL,
+    tags hstore,
+    nodes bigint[]
+);
+
+
+-- Create a table for representing way to node relationships.
+CREATE TABLE way_nodes (
+    way_id bigint NOT NULL,
+    node_id bigint NOT NULL,
+    sequence_id int NOT NULL
+);
+
+
+-- Create a table for relations.
+CREATE TABLE relations (
+    id bigint NOT NULL,
+    version int NOT NULL,
+    user_id int NOT NULL,
+    tstamp timestamp without time zone NOT NULL,
+    changeset_id bigint NOT NULL,
+    tags hstore
+);
+
+-- Create a table for representing relation member relationships.
+CREATE TABLE relation_members (
+    relation_id bigint NOT NULL,
+    member_id bigint NOT NULL,
+    member_type character(1) NOT NULL,
+    member_role text NOT NULL,
+    sequence_id int NOT NULL
+);
+
+
+-- Configure the schema version.
+INSERT INTO schema_info (version) VALUES (6);
+
+
+-- Add primary keys to tables.
+ALTER TABLE ONLY schema_info ADD CONSTRAINT pk_schema_info PRIMARY KEY (version);
+
+ALTER TABLE ONLY users ADD CONSTRAINT pk_users PRIMARY KEY (id);
+
+ALTER TABLE ONLY nodes ADD CONSTRAINT pk_nodes PRIMARY KEY (id);
+
+ALTER TABLE ONLY ways ADD CONSTRAINT pk_ways PRIMARY KEY (id);
+
+ALTER TABLE ONLY way_nodes ADD CONSTRAINT pk_way_nodes PRIMARY KEY (way_id, sequence_id);
+
+ALTER TABLE ONLY relations ADD CONSTRAINT pk_relations PRIMARY KEY (id);
+
+ALTER TABLE ONLY relation_members ADD CONSTRAINT pk_relation_members PRIMARY KEY (relation_id, sequence_id);
+
+
+-- Add indexes to tables.
+CREATE INDEX idx_nodes_geom ON nodes USING gist (geom);
+
+CREATE INDEX idx_way_nodes_node_id ON way_nodes USING btree (node_id);
+
+CREATE INDEX idx_relation_members_member_id_and_type ON relation_members USING btree (member_id, member_type);
+
+
+-- Set to cluster nodes by geographical location.
+ALTER TABLE ONLY nodes CLUSTER ON idx_nodes_geom;
+
+-- Set to cluster the tables showing relationship by parent ID and sequence
+ALTER TABLE ONLY way_nodes CLUSTER ON pk_way_nodes;
+ALTER TABLE ONLY relation_members CLUSTER ON pk_relation_members;
+
+-- There are no sensible CLUSTER orders for users or relations.
+-- Depending on geometry columns different clustings of ways may be desired.
+
+-- Create the function that provides "unnest" functionality while remaining compatible with 8.3.
+CREATE OR REPLACE FUNCTION unnest_bbox_way_nodes() RETURNS void AS $$
+DECLARE
+	previousId ways.id%TYPE;
+	currentId ways.id%TYPE;
+	result bigint[];
+	wayNodeRow way_nodes%ROWTYPE;
+	wayNodes ways.nodes%TYPE;
+BEGIN
+	FOR wayNodes IN SELECT bw.nodes FROM bbox_ways bw LOOP
+		FOR i IN 1 .. array_upper(wayNodes, 1) LOOP
+			INSERT INTO bbox_way_nodes (id) VALUES (wayNodes[i]);
+		END LOOP;
+	END LOOP;
+END;
+$$ LANGUAGE plpgsql;
+
+
+-- Create customisable hook function that is called within the replication update transaction.
+CREATE FUNCTION osmosisUpdate() RETURNS void AS $$
+DECLARE
+BEGIN
+END;
+$$ LANGUAGE plpgsql;
+
+-- Manually set statistics for the way_nodes and relation_members table
+-- Postgres gets horrible counts of distinct values by sampling random pages
+-- and can be off by an 1-2 orders of magnitude
+
+-- Size of the ways table / size of the way_nodes table
+ALTER TABLE way_nodes ALTER COLUMN way_id SET (n_distinct = -0.08);
+
+-- Size of the nodes table / size of the way_nodes table * 0.998
+-- 0.998 is a factor for nodes not in ways
+ALTER TABLE way_nodes ALTER COLUMN node_id SET (n_distinct = -0.83);
+
+-- API allows a maximum of 2000 nodes/way. Unlikely to impact query plans.
+ALTER TABLE way_nodes ALTER COLUMN sequence_id SET (n_distinct = 2000);
+
+-- Size of the relations table / size of the relation_members table
+ALTER TABLE relation_members ALTER COLUMN relation_id SET (n_distinct = -0.09);
+
+-- Based on June 2013 data
+ALTER TABLE relation_members ALTER COLUMN member_id SET (n_distinct = -0.62);
+
+-- Based on June 2013 data. Unlikely to impact query plans.
+ALTER TABLE relation_members ALTER COLUMN member_role SET (n_distinct = 6500);
+
+-- Based on June 2013 data. Unlikely to impact query plans.
+ALTER TABLE relation_members ALTER COLUMN sequence_id SET (n_distinct = 10000);