diff --git c/src/test/isolation/expected/prepared-transactions-2.out i/src/test/isolation/expected/prepared-transactions-2.out new file mode 100644 index 00000000000..f7fd2e7f989 --- /dev/null +++ i/src/test/isolation/expected/prepared-transactions-2.out @@ -0,0 +1,119 @@ +Parsed test spec with 2 sessions + +starting permutation: s1_ins_before s1_begin s1_txid s2_txid s1_update_in s1_ins_in s1_show s1_prepare s1_show s1_commit s1_show +step s1_ins_before: INSERT INTO preptest VALUES ('before'); +step s1_begin: BEGIN TRANSACTION ISOLATION LEVEL READ COMMITTED; +step s1_txid: SELECT txid_current() IS NULL; +?column? + +f +step s2_txid: SELECT txid_current() IS NULL; +?column? + +f +step s1_update_in: UPDATE preptest SET data = 'in; '|| data; +step s1_ins_in: INSERT INTO preptest VALUES ('in'); +step s1_show: SELECT * FROM preptest +data + +in; before +in +step s1_prepare: PREPARE TRANSACTION 'prep'; +step s1_show: SELECT * FROM preptest +data + +before +step s1_commit: COMMIT PREPARED 'prep'; +step s1_show: SELECT * FROM preptest +data + +in; before +in + +starting permutation: s1_ins_before s1_begin s1_txid s2_txid s1_update_in s1_ins_in s1_show s1_prepare s2_show s1_commit s2_show +step s1_ins_before: INSERT INTO preptest VALUES ('before'); +step s1_begin: BEGIN TRANSACTION ISOLATION LEVEL READ COMMITTED; +step s1_txid: SELECT txid_current() IS NULL; +?column? + +f +step s2_txid: SELECT txid_current() IS NULL; +?column? + +f +step s1_update_in: UPDATE preptest SET data = 'in; '|| data; +step s1_ins_in: INSERT INTO preptest VALUES ('in'); +step s1_show: SELECT * FROM preptest +data + +in; before +in +step s1_prepare: PREPARE TRANSACTION 'prep'; +step s2_show: SELECT * FROM preptest +data + +before +step s1_commit: COMMIT PREPARED 'prep'; +step s2_show: SELECT * FROM preptest +data + +in; before +in + +starting permutation: s1_ins_before s1_begin s1_txid s2_txid s1_update_in s1_ins_in s1_show s1_prepare s1_show s1_rollback s1_show +step s1_ins_before: INSERT INTO preptest VALUES ('before'); +step s1_begin: BEGIN TRANSACTION ISOLATION LEVEL READ COMMITTED; +step s1_txid: SELECT txid_current() IS NULL; +?column? + +f +step s2_txid: SELECT txid_current() IS NULL; +?column? + +f +step s1_update_in: UPDATE preptest SET data = 'in; '|| data; +step s1_ins_in: INSERT INTO preptest VALUES ('in'); +step s1_show: SELECT * FROM preptest +data + +in; before +in +step s1_prepare: PREPARE TRANSACTION 'prep'; +step s1_show: SELECT * FROM preptest +data + +before +step s1_rollback: ROLLBACK PREPARED 'prep'; +step s1_show: SELECT * FROM preptest +data + +before + +starting permutation: s1_ins_before s1_begin s1_txid s2_txid s1_update_in s1_ins_in s1_show s1_prepare s2_show s1_rollback s2_show +step s1_ins_before: INSERT INTO preptest VALUES ('before'); +step s1_begin: BEGIN TRANSACTION ISOLATION LEVEL READ COMMITTED; +step s1_txid: SELECT txid_current() IS NULL; +?column? + +f +step s2_txid: SELECT txid_current() IS NULL; +?column? + +f +step s1_update_in: UPDATE preptest SET data = 'in; '|| data; +step s1_ins_in: INSERT INTO preptest VALUES ('in'); +step s1_show: SELECT * FROM preptest +data + +in; before +in +step s1_prepare: PREPARE TRANSACTION 'prep'; +step s2_show: SELECT * FROM preptest +data + +before +step s1_rollback: ROLLBACK PREPARED 'prep'; +step s2_show: SELECT * FROM preptest +data + +before diff --git c/src/test/isolation/isolation_schedule i/src/test/isolation/isolation_schedule index 218c87b24bf..ec15ce784db 100644 --- c/src/test/isolation/isolation_schedule +++ i/src/test/isolation/isolation_schedule @@ -1,3 +1,5 @@ +test: prepared-transactions +test: prepared-transactions-2 test: read-only-anomaly test: read-only-anomaly-2 test: read-only-anomaly-3 diff --git c/src/test/isolation/specs/prepared-transactions-2.spec i/src/test/isolation/specs/prepared-transactions-2.spec new file mode 100644 index 00000000000..d5ed58e4cfc --- /dev/null +++ i/src/test/isolation/specs/prepared-transactions-2.spec @@ -0,0 +1,60 @@ +# This test checks against a bug found in the initial support for +# caching snapshots. The bug caused the snapshot from within the +# to-be-prepared transaction to be used after preparing, erroneously +# not including the prepared transaction's xid, thereby effectively +# treating it as aborted. +# +# See also https://postgr.es/m/E1k7tGP-0005V0-5k%40gemulon.postgresql.org + +setup +{ + CREATE TABLE preptest(data text); +} + +teardown +{ + DROP TABLE preptest; +} + +session "s1" +step "s1_begin" { BEGIN TRANSACTION ISOLATION LEVEL READ COMMITTED; } +step "s1_txid" { SELECT txid_current() IS NULL; } +step "s1_ins_before" { INSERT INTO preptest VALUES ('before'); } +step "s1_update_in" { UPDATE preptest SET data = 'in; '|| data; } +step "s1_ins_in" { INSERT INTO preptest VALUES ('in'); } +step "s1_prepare" { PREPARE TRANSACTION 'prep'; } +step "s1_commit" { COMMIT PREPARED 'prep'; } +step "s1_rollback" { ROLLBACK PREPARED 'prep'; } +step "s1_show" { SELECT * FROM preptest } + +session "s2" +step "s2_show" { SELECT * FROM preptest } +step "s2_txid" { SELECT txid_current() IS NULL; } + +# This permutation shows the bug +permutation "s1_ins_before" "s1_begin" "s1_txid" + # Without acquiring an xid here, s1's xid would be the snapshot's + # xmax, hiding the bug (as only xids < xmax are looked up in ->xip). + "s2_txid" + "s1_update_in" "s1_ins_in" "s1_show" "s1_prepare" + # With the bug the next select would find xmax neither committed nor in progress, + # and therefore mark xmax as invalid. Obviously breaking visibility. + "s1_show" "s1_commit" "s1_show" + +# The following are just variations of the theme that seem good to +# also test, even though they weren't affected by the bug. + +permutation "s1_ins_before" "s1_begin" "s1_txid" + "s2_txid" + "s1_update_in" "s1_ins_in" "s1_show" "s1_prepare" + "s2_show" "s1_commit" "s2_show" + +permutation "s1_ins_before" "s1_begin" "s1_txid" + "s2_txid" + "s1_update_in" "s1_ins_in" "s1_show" "s1_prepare" + "s1_show" "s1_rollback" "s1_show" + +permutation "s1_ins_before" "s1_begin" "s1_txid" + "s2_txid" + "s1_update_in" "s1_ins_in" "s1_show" "s1_prepare" + "s2_show" "s1_rollback" "s2_show"