- mariadb-dump utility performs logical backups by producing
set of sql statements that can be executed. By enabling this
no-autocommit option, InnoDB can load the data in an efficient
way and writes the only one undo log for the whole operation.
Only first insert statement undergoes bulk insert operation,
remaining insert statement doesn't write undo log and undergoes
normal insert code path.
This patch extends the timestamp from
2038-01-19 03:14:07.999999 to 2106-02-07 06:28:15.999999
for 64 bit hardware and OS where 'long' is 64 bits.
This is true for 64 bit Linux but not for Windows.
This is done by treating the 32 bit stored int as unsigned instead of
signed. This is safe as MariaDB has never accepted dates before the epoch
(1970).
The benefit of this approach that for normal timestamp the storage is
compatible with earlier version.
However for tables using system versioning we before stored a
timestamp with the year 2038 as the 'max timestamp', which is used to
detect current values. This patch stores the new 2106 year max value
as the max timestamp. This means that old tables using system
versioning needs to be updated with mariadb-upgrade when moving them
to 11.4. That will be done in a separate commit.
Based on Aleksey Midenkov's patch
mysqldump changes:
* --as-of option specifies historical point;
* query forging protection for --as-of parameter.
system versioned tables are detected by querying I_S.TABLES:
* it transfers much less data when the full table definition is not needed
* it does not give false positives on x TEXT DEFAULT 'WITH SYSTEM VERSIONING'
