* inject portion of time updates into mysql_delete main loop
* triggered case emits delete+insert, no updates
* PORTION OF `SYSTEM_TIME` is forbidden
* `DELETE HISTORY .. FOR PORTION OF ...` is forbidden as well

* add syntax `CREATE TABLE ... PERIOD FOR <apptime>`
* add table period entity

This is done in order to help debugging buildbot failures.

This is follow-up to MDEV-18048: Relax a too strict debug assertion

This assertion should have been relaxed when implementing the first part of
MDEV-15563: instant removal of NOT NULL attribute for ROW_FORMAT=REDUNDANT
tables.

For ROW_FORMAT=REDUNDANT, there is no bitmap of null columns;
the null flags are encoded in the end offset of each field.
We do not really care about the number of fields that can be NULL.

Revert the type casts of 58e525e4.

MariaDB data-at-rest encryption (innodb_encrypt_tables)
had repurposed the same unused data field that was repurposed
in MySQL 5.7 (and MariaDB 10.2) for the Split Sequence Number (SSN)
field of SPATIAL INDEX. Because of this, MariaDB was unable to
support encryption on SPATIAL INDEX pages.

Furthermore, InnoDB page checksums skipped some bytes, and there
are multiple variations and checksum algorithms. By default,
InnoDB accepts all variations of all algorithms that ever existed.
This unnecessarily weakens the page checksums.

We hereby introduce two more innodb_checksum_algorithm variants
(full_crc32, strict_full_crc32) that are special in a way:
When either setting is active, newly created data files will
carry a flag (fil_space_t::full_crc32()) that indicates that
all pages of the file will use a full CRC-32C checksum over the
entire page contents (excluding the bytes where the checksum
is stored, at the very end of the page). Such files will always
use that checksum, no matter what the parameter
innodb_checksum_algorithm is assigned to.

For old files, the old checksum algorithms will continue to be
used. The value strict_full_crc32 will be equivalent to strict_crc32
and the value full_crc32 will be equivalent to crc32.

ROW_FORMAT=COMPRESSED tables will only use the old format.
These tables do not support new features, such as larger
innodb_page_size or instant ADD/DROP COLUMN. They may be
deprecated in the future. We do not want an unnecessary
file format change for them.

The new full_crc32() format also cleans up the MariaDB tablespace
flags. We will reserve flags to store the page_compressed
compression algorithm, and to store the compressed payload length,
so that checksum can be computed over the compressed (and
possibly encrypted) stream and can be validated without
decrypting or decompressing the page.

In the full_crc32 format, there no longer are separate before-encryption
and after-encryption checksums for pages. The single checksum is
computed on the page contents that is written to the file.

We do not make the new algorithm the default for two reasons.
First, MariaDB 10.4.2 was a beta release, and the default values
of parameters should not change after beta. Second, we did not
yet implement the full_crc32 format for page_compressed pages.
This will be fixed in MDEV-18644.

This is joint work with Marko Mäkelä.

For example, with this cmake command line:

cmake . -DCMAKE_C_FLAGS="-DDBUG_ASSERT_AS_PRINTF" \
        -DCMAKE_CXX_FLAGS="-DDBUG_ASSERT_AS_PRINTF"

Apparently DBUG_ASSERT() can co-exist with DBUG_OFF when
-DCMAKE_CXX_FLAGS="-DDBUG_ASSERT_AS_PRINTF".

Removed assertion as it is useless now, since the type is unsigned.

but even if this script called as /bin/mysql_install_db
it is still standard install and scripts are in /usr/share/
(but not in the /share/)
2. fix of bindir path

The replayer did not signal replaying waiters. Added
mysql_cond_broadcast() after replaying is over.

Assertion on client error failed after replay attempt failed due
to certification failure. At this point the transaction does not
go through client state, so the client error cannot be overridden.
Assign ER_LOCK_DEADLOCK to thd directly instead.

Use timed cond wait when waiting for replayers to finish and
check if the transaction has been BF aborted during the wait.

Transaction XID is not initialized before transaction is started.

Temporary disable WSREP while executing RESET MASTER. In situation when 2 nodes are both master/slave first stop slave on both and than reset master.
Enforce stricter causality check with wsrep_sync_wait.

Check for garbd executable on different paths. If not found terminate test.

Optimized the code that removed multiple equalities pushed from HAVING
into WHERE. Now this removal is postponed until all multiple equalities
are eliminated in substitute_for_best_equal_field().

trx_rseg_t::is_persistent(): Correct a bogus debug assertion.

When sampling data through ANALYZE TABLE, use the estimator to get a
better estimation of avg_frequency instead of just using the raw sampled data.

The variable controls the amount of sampling analyze table performs.

If ANALYZE table with histogram collection is too slow, one can reduce the
time taken by setting analyze_sample_percentage to a lower value of the
total number of rows.
Setting it to 0 will use a formula to compute how many rows to sample:

The number of rows collected is capped to a minimum of 50000 and
increases logarithmically with a coffecient of 4096. The coffecient is
chosen so that we expect an error of less than 3% in our estimations
according to the paper:
"Random Sampling for Histogram Construction: How much is enough?”
– Surajit Chaudhuri, Rajeev Motwani, Vivek Narasayya, ACM SIGMOD, 1998.

The drawback of sampling is that avg_frequency number is computed
imprecisely and will yeild a smaller number than the real one.

The add method does not need to provide the row order number. It was
only used to detect if the minimum/maximum value was populated once or not, so
as to force an update for the first encounter of a value.

log_group_read_log_seg(): Always return false when returning
before reading end_lsn.

xtrabackup_copy_logfile(): On error, indicate whether
a corrupt log record was encountered.

Only xtrabackup_copy_logfile() in Mariabackup cared about the
return value of the function. InnoDB crash recovery was not
affected by this bug.

Remove CMake INSTALL command for COMPONENT DataFiles.

mysql_install_db.exe will calculate default datadir, so that it can be
called without any parameters.

The value for eq_range_index_dive_limit is increased to 200.

optimize_join_buffer_size is switched ON.

By pure chance the macro worked in the cases it was used, but
better to get this fixed!