use the original, not the truncated, field in the long unique prefix,
that is, in the hash(left(field, length)) expression.

because MyISAM CHECK/REPAIR in compute_vcols() moves table->field
but not prefix fields from keyparts.

Also, implement Field_string::cmp_prefix() for prefix comparison
of CHAR columns to work.

no need to use it when both arguments have the same length

use thd->start_time for the "start_time" column of the slow_log table.
"current_time" here refers to the current_time() function return value
not to the actual *current* time.

also fixes
MDEV-33267 User with minimal permissions can intentionally corrupt mysql.slow_log table

should fix numerous failures of main.bootstrap tets

Item_func_quote did not calculate its max_length correctly for nullable
arguments.

Fix:

In case if the argument is nullable, reserve at least 4 characters
so the string "NULL" fits.

MCOL-5611 supporting with Boost-1.80, the version "next_prime"
disappears from https://github.com/boostorg/unordered/blob/boost-1.79.0/include/boost/unordered/detail/implementation.hpp
makes it the currenly highest supported versions.

Lets check this version.

While CMake-3.19+ supports version ranges in package determinations this
isn't supported for Boost in Cmake-3.28. So we check for the 1.80 and
don't compile ColumnStore.

Statements affect by this bug are all SQL statements that
1) prefixed with "EXPLAIN"
2) have a lower level join structure created for a union subquery.

A bug in select_describe() passed an incorrect "result" object to
mysql_explain_union(), resulting in unpredictable behaviour and
out of context calls.

Reviewed by: Oleksandr Byelkin, sanja@mariadb.com

An existing binlog checksum can be overridden to 0 if writing a NULL
payload when using Zlib for the computation. That is, calling into
Zlib's crc32 with empty data initializes an incremental CRC
computation to 0.

This patch changes the Log_event_writer::write_data() to exit
immediately if there is nothing to write, thereby bypassing the
checksum computation. This follows the pattern of
Log_event_writer::encrypt_and_write(), which also exits immediately
if there is no data to write.

Reviewed By:
============
Andrei Elkin <andrei.elkin@mariadb.com>

MDEV-32968  InnoDB fails to restore tablespace first page from doublewrite buffer when page is empty

recv_dblwr_t::find_first_page(): Free the allocated memory
to read the first 3 pages from tablespace.

innodb.doublewrite: Added sleep to ensure page cleaner thread
wake up from my_cond_wait

Adding GEOMETRY type user variables.

MDEV-32968  InnoDB fails to restore tablespace first page from doublewrite buffer when page is empty

- InnoDB fails to find the space id from the page0 of
the tablespace. In that case, InnoDB can use
doublewrite buffer to recover the page0 and write
into the file.

- buf_dblwr_t::init_or_load_pages(): Loads only the pages
which are valid.(page lsn >= checkpoint). To do that,
InnoDB has to open the redo log before system
tablespace, read the latest checkpoint information.

recv_dblwr_t::find_first_page():
1) Iterate the doublewrite buffer pages and find the 0th page
2) Read the tablespace flags, space id from the 0th page.
3) Read the 1st, 2nd and 3rd page from tablespace file and
compare the space id with the space id which is stored
in doublewrite buffer.
4) If it matches then we can write into the file.
5) Return space which matches the pages from the file.

SysTablespace::read_lsn_and_check_flags(): Remove the
retry logic for validating the first page. After
restoring the first page from doublewrite buffer,
assign tablespace flags by reading the first page.

recv_recovery_read_max_checkpoint(): Reads the maximum
checkpoint information from log file

recv_recovery_from_checkpoint_start(): Avoid reading
the checkpoint header information from log file

Datafile::validate_first_page(): Throw error in case
of first page validation fails.

Upstream Debian Sid which will become Debian Trixie (13)
have dropped NCurses version 5 and changed dev package name just
libncurses-dev

Add INSERT ... SELECT to the list of commands that can be traced

Approved by Sergei Petrunia (sergey@mariadb.com)

The problem is the test is skipped after sourcing include/master-slave.inc.
This leaves the slave threads running after the test is skipped, causing a
following test to fail during rpl setup.

Also rename have_normal_bzip.inc to the more appropriate _zlib.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

- Closes PR #2839
- Usage of `Column_definition_fix_attributes()` suggested by Alexandar
  Barkov - thanks bar, that is better than hook in server code
  (reverted 22f3ebe4)
  - This method is called after parsing the data type:
    * in `CREATE/ALTER TABLE`
    * in SP: return data type, parameter data type, variable data type
  - We want to disallow all these use cases of MYSQL_JSON.

- Reviewer: bar@mariadb.com
            cvicentiu@mariadb.org

This reverts commit 22f3ebe4.

Closes PR #2839
Reviewer: cvicentiu@mariadb.org

- We don't test `json` MySQL tables from `std_data` since the error `ER_TABLE_NEEDS_REBUILD
` is invoked. However MDEV-32235 will override this test after merge,
but leave it to show behavior and historical changes.

- Closes PR #2833
Reviewer: <cvicentiu@mariadb.org>
          <serg@mariadb.com>

All Spider tables are recorded in the system table
mysql.spider_tables. Deleting a spider table removes the corresponding
rows from the system table, among other things. This patch makes it so
that if spider could not find any record in the system table to delete
for a given table, it should correctly report that no such Spider
table exists.

The field is assigned but unused, and it causes heap-use-after-free.

remove thr_setconcurrency()
followup for 8bbcaab1

Fix by Rainer Orth

mark auto-inc columns for read/write on INSERT,
but only for read on UPDATE

When the host is not specified, it defaults to localhost.

A new column was introduced to the show index output in 10.6 in
f691d986

Thus we update the check of the number of columns to be at least 13,
rather than exactly 13.

Also backport an err number and format from 10.5 for better error
messages when the column number is wrong.

There are a large number of uses of `strerror` in the codebase,
the local declaration in `storage/connect/tabvct.cpp` is the only one.

Given that none is needed elsewhere, I conclude that this instance can
simply be removed.

initialize THD::rand in THD::init() not in THD::THD(),
because the former is also called when a THD is reused -
in COM_CHANGE_USER and in taking a THD from the cache.

Also use current cycle timer for more unpreditability

Item_float::neg() did not preserve the "presentation" from "this".
So
  CAST(-1e0 AS UNSIGNED)  -- cast from double to unsigned
changes its meaning to:
  CAST(-1 AS UNSIGNED)  -- cast signed to undigned

Fixing Item_float::neg() to construct the new value for
Item_float::presentation as follows:
- if the old value starts with minus, then the minus is truncated:
  '-2e0' -> '2e0'
- otherwise, minus sign followed by its old value:
  '1e0'  -> '-1e0'

The bitmap is temporarily flipped to ~0 for the sake of checking all
fields. It needs to be restored because it will be reused in second
and subsequent ps execution.

Fix by Rainer Orth

Fix by Rainer Orth

With the result like

encryption.innochecksum 'debug'   [ skipped ] combination not found

instead of

*** ERROR: Could not run encryption.innochecksum with 'debug' combination(s)

buf_flush_page_cleaner(): A continue or break inside DBUG_EXECUTE_IF
actually is a no-op. Use an explicit call to _db_keyword_() to
actually avoid advancing the checkpoint.

buf_flush_list_now_set(): Invoke os_aio_wait_until_no_pending_writes()
to ensure that the page write to the system tablespace is completed.

In commit b4ff6456 the
signature of mysql_show_var_func was changed, but not all functions
of that type were adjusted.

When the server is configured with `cmake -DWITH_ASAN=ON` and
compiled with clang, runtime errors would be flagged for invoking
functions through an incompatible function pointer.

Reviewed by: Michael 'Monty' Widenius

If a query contained a CTE whose name coincided with the name of one of
the base tables used in the specification of the CTE and the query had at
least two references to this CTE in the specifications of other CTEs then
processing of the query led to unlimited recursion that ultimately caused
a crash of the server.

Any secondary non-recursive reference to a CTE requires creation of a copy
of the CTE specification. All the references to CTEs in this copy must be
resolved. If the specification contains a reference to a base table whose
name coincides with the name of then CTE then it should be ensured that
this reference in no way can be resolved against the name of the CTE.

srv_start(): Move a read only mode startup tweak from
innodb_init_params() to the correct location. Also if
innodb_force_recovery=6 we will disable the doublewrite buffer,
because InnoDB must run in read-only mode to prevent further corruption.

This change only affects debug checks. Whenever srv_read_only_mode holds,
the buf_pool.flush_list will be empty, that is, there will be no writes
of persistent InnoDB data pages.

Reviewed by: Thirunarayanan Balathandayuthapani