rollback; drop table if exists hs_hosting_asset_versions; drop table if exists hs_hosting_asset_ex; drop view if exists hs_hosting_asset_hv; drop procedure if exists tx_create_historicization; drop view if exists tx_create_historical_view; drop function if exists tx_historicize_tf(); drop type if exists tx_operation; -- ======================================================== -- Historization -- -------------------------------------------------------- -- FIXME: Liquibase-integration create type "tx_operation" as enum ('INSERT', 'UPDATE', 'DELETE', 'TRUNCATE'); create or replace function tx_historicize_tf() returns trigger language plpgsql strict as $$ declare currentUser varchar(63); currentTask varchar(127); "row" record; "alive" boolean; "sql" varchar; begin -- determine user_id begin currentUser := current_setting('hsadminng.currentUser'); exception when others then currentUser := null; end; if (currentUser is null or currentUser = '') then raise exception 'hsadminng.currentUser must be defined, please use "SET LOCAL ...;"'; end if; raise notice 'currentUser: %', currentUser; -- determine task currentTask = current_setting('hsadminng.currentTask'); assert currentTask is not null and length(currentTask) >= 12, format('hsadminng.currentTask (%s) must be defined and min 12 characters long, please use "SET LOCAL ...;"', currentTask); assert length(currentTask) <= 127, format('hsadminng.currentTask (%s) must not be longer than 127 characters"', currentTask); if (TG_OP = 'INSERT') or (TG_OP = 'UPDATE') then "row" := NEW; "alive" := true; else -- DELETE or TRUNCATE "row" := OLD; "alive" := false; end if; sql := format('INSERT INTO %3$I_ex VALUES (DEFAULT, txid_current(), %1$L, %2$L, $1.*)', TG_OP, alive, TG_TABLE_NAME); raise notice 'sql: %', sql; execute sql using "row"; return "row"; end; $$; create or replace procedure tx_create_historical_view(baseTable varchar) language plpgsql as $$ declare createTriggerSQL varchar; viewName varchar; exVersionsTable varchar; createViewSQL varchar; baseCols varchar; begin viewName = quote_ident(format('%s_hv', baseTable)); exVersionsTable = quote_ident(format('%s_ex', baseTable)); baseCols = (select string_agg(quote_ident(column_name), ', ') from information_schema.columns where table_schema = 'public' and table_name = baseTable); createViewSQL = format( 'CREATE OR REPLACE VIEW %1$s AS' || '(' || ' SELECT %2$s' || ' FROM %3$s' || ' WHERE alive = TRUE' || ' AND version_id IN' || ' (' || ' SELECT max(ex.version_id) AS history_id' || ' FROM %3$s AS ex' || ' JOIN tx_context as txc ON ex.txid = txc.txid' || ' WHERE txc.txtimestamp <= current_setting(''hsadminng.tx_history_timestamp'')::timestamp' || ' OR txc.txid = current_setting(''hsadminng.tx_history_txid'')' || ' GROUP BY uuid' || ' )' || ')', viewName, baseCols, exVersionsTable ); raise notice 'sql: %', createViewSQL; execute createViewSQL; createTriggerSQL = 'CREATE TRIGGER ' || baseTable || '_tx_historicize_tf' || ' AFTER INSERT OR DELETE OR UPDATE ON ' || baseTable || ' FOR EACH ROW EXECUTE PROCEDURE tx_historicize_tf()'; raise notice 'sql: %', createTriggerSQL; execute createTriggerSQL; end; $$; create or replace procedure tx_create_historicization(baseTable varchar) language plpgsql as $$ declare createHistTableSql varchar; createTriggerSQL varchar; viewName varchar; exVersionsTable varchar; createViewSQL varchar; baseCols varchar; begin -- create the history table createHistTableSql = '' || 'CREATE TABLE ' || baseTable || '_ex (' || ' version_id serial PRIMARY KEY,' || ' txid bigint NOT NULL REFERENCES tx_context(txid),' || ' trigger_op tx_operation NOT NULL,' || ' alive boolean not null,' || ' LIKE ' || baseTable || ' EXCLUDING CONSTRAINTS' || ' EXCLUDING STATISTICS' || ')'; raise notice 'sql: %', createHistTableSql; execute createHistTableSql; -- create the historical view viewName = quote_ident(format('%s_hv', baseTable)); exVersionsTable = quote_ident(format('%s_ex', baseTable)); baseCols = (select string_agg(quote_ident(column_name), ', ') from information_schema.columns where table_schema = 'public' and table_name = baseTable); createViewSQL = format( 'CREATE OR REPLACE VIEW %1$s AS' || '(' || ' SELECT %2$s' || ' FROM %3$s' || ' WHERE alive = TRUE' || ' AND version_id IN' || ' (' || ' SELECT max(ex.version_id) AS history_id' || ' FROM %3$s AS ex' || ' JOIN tx_context as txc ON ex.txid = txc.txid' || ' WHERE txc.txtimestamp <= current_setting(''hsadminng.tx_history_timestamp'')::timestamp' || ' GROUP BY uuid' || ' )' || ')', viewName, baseCols, exVersionsTable ); raise notice 'sql: %', createViewSQL; execute createViewSQL; createTriggerSQL = 'CREATE TRIGGER ' || baseTable || '_tx_historicize_tf' || ' AFTER INSERT OR DELETE OR UPDATE ON ' || baseTable || ' FOR EACH ROW EXECUTE PROCEDURE tx_historicize_tf()'; raise notice 'sql: %', createTriggerSQL; execute createTriggerSQL; end; $$; --- ================================================== call tx_create_historicization('hs_hosting_asset'); -- and expanded: -- =========================================================================================== rollback; begin transaction; call defineContext('historization testing', null, 'superuser-alex@hostsharing.net', 'hs_booking_project#D-1000000-hshdefaultproject:ADMIN'); -- prod+test -- 'hs_booking_project#D-1000300-mihdefaultproject:ADMIN'); -- prod -- 'hs_booking_project#D-1000300-mimdefaultproject:ADMIN'); -- test -- update hs_hosting_asset set caption='lug00 b' where identifier = 'lug00' and type = 'MANAGED_WEBSPACE'; -- prod update hs_hosting_asset set caption='mim00 A ' || now()::text where identifier = 'mim00' and type = 'MANAGED_WEBSPACE'; -- test update hs_hosting_asset set caption='mim00 B ' || now()::text where identifier = 'mim00' and type = 'MANAGED_WEBSPACE'; -- test commit; -- single version at point in time -- set hsadminng.tx_history_timestamp to '2024-08-27 07:44:03'; -- UTC set hsadminng.tx_history_timestamp to '2024-08-27 07:44:03'; -- UTC select uuid, version, identifier, caption from hs_hosting_asset_hv p where identifier in ('lug00', 'mim00'); -- all versions select txc.txtimestamp, txc.currentUser, txc.currentTask, haex.* from hs_hosting_asset_ex haex join tx_context txc on haex.txid=txc.txid where haex.identifier in ('lug00', 'mim00');