chore: import upstream snapshot with attribution

2026-07-13 12:32:25 +08:00
commit e014feafe1
2285 changed files with 1131979 additions and 0 deletions
@@ -0,0 +1,102 @@
+-- txid_snapshot data type and related functions
+-- Note: these are backward-compatibility functions and types, and have been
+-- replaced by new xid8-based variants.  See xid.sql.  The txid variants will
+-- be removed in a future release.
+
+-- i/o
+select '12:13:'::txid_snapshot;
+select '12:18:14,16'::txid_snapshot;
+select '12:16:14,14'::txid_snapshot;
+
+-- errors
+select '31:12:'::txid_snapshot;
+select '0:1:'::txid_snapshot;
+select '12:13:0'::txid_snapshot;
+select '12:16:14,13'::txid_snapshot;
+
+create temp table snapshot_test (
+	nr	integer,
+	snap	txid_snapshot
+);
+
+insert into snapshot_test values (1, '12:13:');
+insert into snapshot_test values (2, '12:20:13,15,18');
+insert into snapshot_test values (3, '100001:100009:100005,100007,100008');
+insert into snapshot_test values (4, '100:150:101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131');
+select snap from snapshot_test order by nr;
+
+select  txid_snapshot_xmin(snap),
+	txid_snapshot_xmax(snap),
+	txid_snapshot_xip(snap)
+from snapshot_test order by nr;
+
+select id, txid_visible_in_snapshot(id, snap)
+from snapshot_test, generate_series(11, 21) id
+where nr = 2;
+
+-- test bsearch
+select id, txid_visible_in_snapshot(id, snap)
+from snapshot_test, generate_series(90, 160) id
+where nr = 4;
+
+-- test current values also
+select txid_current() >= txid_snapshot_xmin(txid_current_snapshot());
+
+-- we can't assume current is always less than xmax, however
+
+select txid_visible_in_snapshot(txid_current(), txid_current_snapshot());
+
+-- test 64bitness
+
+select txid_snapshot '1000100010001000:1000100010001100:1000100010001012,1000100010001013';
+select txid_visible_in_snapshot('1000100010001012', '1000100010001000:1000100010001100:1000100010001012,1000100010001013');
+select txid_visible_in_snapshot('1000100010001015', '1000100010001000:1000100010001100:1000100010001012,1000100010001013');
+
+-- test 64bit overflow
+SELECT txid_snapshot '1:9223372036854775807:3';
+SELECT txid_snapshot '1:9223372036854775808:3';
+
+-- test txid_current_if_assigned
+BEGIN;
+SELECT txid_current_if_assigned() IS NULL;
+SELECT txid_current() \gset
+SELECT txid_current_if_assigned() IS NOT DISTINCT FROM BIGINT :'txid_current';
+COMMIT;
+
+-- test xid status functions
+BEGIN;
+SELECT txid_current() AS committed \gset
+COMMIT;
+
+BEGIN;
+SELECT txid_current() AS rolledback \gset
+ROLLBACK;
+
+BEGIN;
+SELECT txid_current() AS inprogress \gset
+
+SELECT txid_status(:committed) AS committed;
+SELECT txid_status(:rolledback) AS rolledback;
+SELECT txid_status(:inprogress) AS inprogress;
+SELECT txid_status(1); -- BootstrapTransactionId is always committed
+SELECT txid_status(2); -- FrozenTransactionId is always committed
+SELECT txid_status(3); -- in regress testing FirstNormalTransactionId will always be behind oldestXmin
+
+COMMIT;
+
+BEGIN;
+CREATE FUNCTION test_future_xid_status(bigint)
+RETURNS void
+LANGUAGE plpgsql
+AS
+$$
+BEGIN
+  PERFORM txid_status($1);
+  RAISE EXCEPTION 'didn''t ERROR at xid in the future as expected';
+EXCEPTION
+  WHEN invalid_parameter_value THEN
+    RAISE NOTICE 'Got expected error for xid in the future';
+END;
+$$;
+SELECT test_future_xid_status(:inprogress + 10000);
+ROLLBACK;