-- txid_snapshot data type and related functions -- 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';