Fix possible inconsistency between bitmap LOV table and index #838
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my-ship-it
previously approved these changes
Jan 3, 2025
There was an issue reported and fixed by #11378 where the `kill_9_segment_processes` function had a bug and could not get the postgres pids to kill (more details in the mentioned PR). Even though the fix was correct, it has some issues -
- It is not reliable to use the grep command `ps ux | grep "[p]ostgres:\s*%s" | awk \'{print $2}\'` to get a list of postgres processes since the pattern can be changed in the future and the output of the command also depends on the OS.
- The function never considered the case for executing on remote hosts. So the function would never work in case of standby shutdown when standby is on another host.
To address the above issues following changes are made -
- Use the postmaster pid to get the list of all its child processes (implemented using `get_postgres_segment_processes`) before stopping the postgres server which will be used by the `kill_9_segment_processes` function at the end instead of the grep command.
- Modify the `kill_9_segment_processes` so that it can be executed remotely as well.
Before this commit, Greenplum didn't take `internalPQconninfoOption` and `PQconninfoOption` differently on the backend side, that's why we had `connofs` in `PQconninfoOption`, nowadays it's not needed and not actually being used, just remove. commit 510a20b Author: Adam Lee <[email protected]> Date: Mon Oct 23 14:40:11 2017 +0800 Retire gp_libpq_fe part 1, libpq itself
The workflow of `mop_high_watermark` was not clear enough that I thought it's useless, add some comments for others.
Use TRUSTED_SHELL in configuration file when gpinitsystem.
Fix bug of upstream merged feature COMMIT AND CHAIN in GPDB. The feature has been supported by upstream in https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=280a408b48d5ee42969f981bceb9e9426c3a344c We need to adapt distributed transaction block Context/State for supporting this feature in MPP. As a result, In this PR, we tried to set up DtxContext again before start a "chain" transaction for keeping correct distributed Context in a new transaction block state, and that is same as what we did in StartTransactionCommand(). List some of block state that we need to setup DtxContext for chain transaction: TBLOCK_END TBLOCK_ABORT_END TBLOCK_ABORT_PENDING TBLOCK_SUBCOMMIT
When we build a bitmap index on a heap table, we need to scan all the tuples. Usually, it'll start at block 0 to the end. But if we allow sync scan, it'll scan the table circularly, from block X up to the end and then from block 0 to X-1, to ensure we visit all rows while still participating in the common scan. This could lead tids are not in order when building bitmap index, which will throw an error in the current implementation. So this PR forbids sync scan when building bitmap index. Besides the above fact, if we build bitmap index on a heap table, there could have HOT-chain, and it'll return the root tuple's tid, which could lead to the TIDs we scanned are not in order.
If DELETE operator is generated by SplitUpdate node (SplitUpdate node is generated for updating the partition keys), we raise an error. The root cause is SplitUpdate will split the origin tuple to two tuples, one is for deleting and the other one is for inserting. we can skip the deleting tuple if we found the tuple is updated concurrently by another transaction, but it is difficult to skip the inserting tuple, so it will leads to more tuples after updating.
yjhjstz
approved these changes
Jan 3, 2025
my-ship-it
approved these changes
Jan 7, 2025
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Fixes #ISSUE_Number
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make installcheckmake -C src/test installcheck-cbdb-parallelImpact
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