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-- init
\set ECHO none
-- i/o
select '12:13:'::txid_snapshot;
txid_snapshot
---------------
12:13:
(1 row)
select '12:13:1,2'::txid_snapshot;
ERROR: illegal txid_snapshot input format
-- errors
select '31:12:'::txid_snapshot;
ERROR: illegal txid_snapshot input format
select '0:1:'::txid_snapshot;
ERROR: illegal txid_snapshot input format
select '12:13:0'::txid_snapshot;
ERROR: illegal txid_snapshot input format
select '12:13:2,1'::txid_snapshot;
ERROR: illegal txid_snapshot input format
create 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');
select snap from snapshot_test order by nr;
snap
------------------------------------
12:13:
12:20:13,15,18
100001:100009:100005,100007,100008
(3 rows)
select txid_snapshot_xmin(snap),
txid_snapshot_xmax(snap),
txid_snapshot_xip(snap)
from snapshot_test order by nr;
txid_snapshot_xmin | txid_snapshot_xmax | txid_snapshot_xip
--------------------+--------------------+-------------------
12 | 20 | 13
12 | 20 | 15
12 | 20 | 18
100001 | 100009 | 100005
100001 | 100009 | 100007
100001 | 100009 | 100008
(6 rows)
select id, txid_visible_in_snapshot(id, snap)
from snapshot_test, generate_series(11, 21) id
where nr = 2;
id | txid_visible_in_snapshot
----+--------------------------
11 | t
12 | t
13 | f
14 | t
15 | f
16 | t
17 | t
18 | f
19 | t
20 | f
21 | f
(11 rows)
-- test current values also
select txid_current() >= txid_snapshot_xmin(txid_current_snapshot());
?column?
----------
t
(1 row)
-- select txid_current_txid() < txid_snapshot_xmax(txid_current_snapshot());
-- select txid_in_snapshot(txid_current_txid(), txid_current_snapshot()),
-- txid_not_in_snapshot(txid_current_txid(), txid_current_snapshot());
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