hostsharing/hs.hsadmin.ng
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extract tx_history_txid() into a CTE-query

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Michael Hoennig 2024-08-27 20:03:03 +02:00
parent 6f740c7209
commit 2f198664fa
1 changed files with 38 additions and 12 deletions
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50
sql/historization.sql
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@ -15,6 +15,30 @@ drop type if exists tx_operation;
create type "tx_operation" as enum ('INSERT', 'UPDATE', 'DELETE', 'TRUNCATE');
create or replace function tx_history_txid()
returns xid8 stable
language plpgsql as $$
declare
historicalTxIdSetting text;
historicalTxId xid8;
historicalTimestamp timestamp;
begin
select current_setting('hsadminng.tx_history_txid', true) into historicalTxIdSetting;
raise notice 'tx_history_txid(): historicalTxIdSetting=%', historicalTxIdSetting;
if historicalTxIdSetting is null or historicalTxIdSetting = '' then
select current_setting('hsadminng.tx_history_timestamp', true)::timestamp into historicalTimestamp;
raise notice 'tx_history_txid(): historicalTimestamp=%', historicalTimestamp;
select max(txc.txid) from tx_context txc where txc.txtimestamp <= historicalTimestamp into historicalTxId;
raise notice 'tx_history_txid(): historicalTxId=%', historicalTxId;
else
historicalTxId = historicalTxIdSetting::xid8;
end if;
return historicalTxId;
end; $$;
create or replace function tx_historicize_tf()
returns trigger
language plpgsql
@ -97,6 +121,8 @@ begin
createViewSQL = format(
'CREATE OR REPLACE VIEW %1$s AS' ||
'(' ||
-- make sure the function is only called once, not for every matching row in tx_context
' WITH txh AS (SELECT tx_history_txid() AS txid) ' ||
' SELECT %2$s' ||
' FROM %3$s' ||
' WHERE alive = TRUE' ||
@ -105,7 +131,7 @@ begin
' SELECT max(ex.version_id) AS history_id' ||
' FROM %3$s AS ex' ||
' JOIN tx_context as txc ON ex.txid = txc.txid' ||
' WHERE txc.txid = current_setting(''hsadminng.tx_history_txid'', true)::xid8' ||
' WHERE txc.txid <= (SELECT txid FROM txh)' ||
' GROUP BY uuid' ||
' )' ||
')',
@ -126,8 +152,6 @@ end; $$;
call tx_create_historicization('hs_hosting_asset'); -- FIXME: move to 7010-hosting-asset.sql
-- and expanded:
-- ===========================================================================================
@ -138,19 +162,21 @@ call defineContext('historization testing', null, 'superuser-alex@hostsharing.ne
-- '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='hsh00 E ' || now()::text where identifier = 'hsh00' and type = 'MANAGED_WEBSPACE'; -- test
update hs_hosting_asset set caption='hsh00 F ' || now()::text where identifier = 'hsh00' and type = 'MANAGED_WEBSPACE'; -- test
update hs_hosting_asset set caption='hsh00 C ' || now()::text where identifier = 'hsh00' and type = 'MANAGED_WEBSPACE'; -- test
update hs_hosting_asset set caption='hsh00 D ' || now()::text where identifier = 'hsh00' and type = 'MANAGED_WEBSPACE'; -- test
commit;
-- single version at point in time
-- set hsadminng.tx_history_txid to (select max(txid) from tx_context where txtimestamp<='2024-08-27 12:13:13.450821');
SELECT set_config('hsadminng.tx_history_txid', (select max(txid)::Text from tx_context where txtimestamp<='2024-08-27 12:13:13.450821'), FALSE);
select uuid, version, identifier, caption from hs_hosting_asset_hv p where identifier in ('hsh00');
set hsadminng.tx_history_txid to '3249';
--set hsadminng.tx_history_timestamp to '2024-08-27 17:52:07.755407';
-- all versions
select tx_history_txid(), 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 ('hsh00', 'mim00');
select uuid, version, identifier, caption from hs_hosting_asset_hv p where identifier in ('hsh00', 'mim00');
select pg_current_xact_id();
-- 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 ('hsh00');