Change names of functions not returning Json.
  modified:   storage/connect/json.cpp
  modified:   storage/connect/json.h
  modified:   storage/connect/jsonudf.cpp
  modified:   storage/connect/jsonudf.h
  modified:   storage/connect/mysql-test/connect/r/json_udf.result
  modified:   storage/connect/plugutil.c
  modified:   storage/connect/value.cpp
  modified:   storage/connect/value.h

Fix wrong calling sequence for RESULT_INT and RESULT_REAL functions.
  modified:   storage/connect/jsonudf.cpp
  modified:   storage/connect/jsonudf.h

  modified:   storage/connect/jsonudf.cpp

Record result of json test
  modified:   storage/connect/mysql-test/connect/r/json.result

  modified:   storage/connect/noconst.c

Fix a few bugs in json udf's.
  modified:   storage/connect/jsonudf.cpp

  modified:   storage/connect/json.cpp
  modified:   storage/connect/json.h
  modified:   storage/connect/jsonudf.cpp
  modified:   storage/connect/jsonudf.h

  modified:   storage/connect/json.cpp
  modified:   storage/connect/json.h
  modified:   storage/connect/jsonudf.cpp
  modified:   storage/connect/mysql-test/connect/r/json_udf.result
  modified:   storage/connect/mysql-test/connect/t/json.test
  modified:   storage/connect/tabjson.cpp

Fix wrong calculation of Estimated Length when the table has virtual or special columns
  modified:   storage/connect/reldef.h
  modified:   storage/connect/tabdos.cpp

Fix wrong handling of null values in ODBCCOL::ReadColumn
  modified:   storage/connect/tabodbc.cpp

Fix crash when SetValue_char is called with a negative length value.
This can happen in odbconn.cpp when SQLFetch returns SQL_NO_TOTAL (-4) as length.
  modified:   storage/connect/odbconn.cpp
  modified:   storage/connect/value.cpp

  modified:   storage/connect/jsonudf.cpp

- Apply to ODBC tables as well as MYSQL tables
- Fix and enhance the CheckCond routine
  Make ReadKey and MakeKeyWhere handle all conditions
  modified:   storage/connect/.gitattributes
  modified:   storage/connect/.gitignore
  modified:   storage/connect/connect.cc
  modified:   storage/connect/connect.h
  modified:   storage/connect/ha_connect.cc
  modified:   storage/connect/ha_connect.h
  modified:   storage/connect/mycat.cc
  modified:   storage/connect/tabmysql.cpp
  modified:   storage/connect/tabmysql.h
  modified:   storage/connect/tabodbc.cpp
  modified:   storage/connect/tabodbc.h
  modified:   storage/connect/xobject.cpp
  modified:   storage/connect/xobject.h
  modified:   storage/connect/xtable.h

Add some new tests:
  storage/connect/mysql-test/connect/r/endian.result
  storage/connect/mysql-test/connect/r/mysql_index.result
  storage/connect/mysql-test/connect/t/endian.test
  storage/connect/mysql-test/connect/t/mysql_index.test

MDEV-8250: InnoDB: Page compressed tables are not compressed and compressed+encrypted tables cause crash

Analysis: Problem is that both encrypted tables and compressed tables use
FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION to store
required metadata. Furhermore, for only compressed tables currently
code skips compression.

Fixes:
- Only encrypted pages store key_version to FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION,
  no need to fix
- Only compressed pages store compression algorithm to FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION,
  no need to fix as they have different page type FIL_PAGE_PAGE_COMPRESSED
- Compressed and encrypted pages now use a new page type FIL_PAGE_PAGE_COMPRESSED_ENCRYPTED and
  key_version is stored on FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION and compression
  method is stored after FIL header similar way as compressed size, so that first
  FIL_PAGE_COMPRESSED_SIZE is stored followed by FIL_PAGE_COMPRESSION_METHOD
- Fix buf_page_encrypt_before_write function to really compress pages if compression is enabled
- Fix buf_page_decrypt_after_read function to really decompress pages if compression is used
- Small style fixes

Fix typo error in CntIndexRange (kp instead of p)
Change version date
  modified:   storage/connect/connect.cc
  modified:   storage/connect/ha_connect.cc

return unsigned, not signed.
return a value large enough for GCM

and don't recommend aes_ctr if it's unavailable

introduce ENCRYPTION_KEY_SYSTEM_DATA and
ENCRYPTION_KEY_TEMPORARY_DATA constants; use them everywhere.

IO_CACHE tempfiles encryption

when working with IO_CACHE's, don't access IO_CACHE::file directly

* remove unused (and not implemented) WRITE_NET type
* remove cast in my_b_write() macro. my_b_* macros are
  function-like, casts are responsibility of the caller
* replace hackish _my_b_write(info,0,0) with the explicit
  my_b_flush_io_cache() in my_b_write_byte()
* remove unused my_b_fill_cache()
* replace pbool -> my_bool
* make internal IO_CACHE functions static
* reformat comments, correct typos, remove obsolete comments (ISAM)
* assert valid cache type in init_functions()
* use IO_ROUND_DN() macro where appropriate
* remove unused DBUG_EXECUTE_IF in _my_b_cache_write()
* remove unnecessary __attribute__((unused))
* fix goto error in parse_file.cc
* remove redundant reinit_io_cache() in uniques.cc
* don't do reinit_io_cache() if the cache was not initialized
  in ma_check.c
* extract duplicate functionality from various _my_b_*_read
  functions into a common wrapper. Same for _my_b_*_write
* create _my_b_cache_write_r instead of having if's in
  _my_b_cache_write (similar to existing _my_b_cache_read and
  _my_b_cache_read_r)
* don't call mysql_file_write() from my_b_flush_io_cache(),
  call info->write_function() instead

that is, don't create a "temporary" IO_CACHE with file==-1
and manually swap it later to the valid file descriptor.

remove some 14-year old code that added support for
LOAD DATA replication to IO_CACHE:
* three callbacks, of which only two were actually used and that
  were only needed for LOAD DATA replication but were
  tested in every IO_CACHE instance
* an additional opaque void * argument in IO_CACHE, also only
  used for LOAD DATA replication, but present everywhere
* the code to close IO_CACHE prematurely in LOAD DATA to have
  these callbacks called in the correct order and a long
  comment explaining what will happen if IO_CACHE is not
  closed prematurely
* a variable to track whether IO_CACHE was closed prematurely
  (to avoid double-closing it)

perfschema after 5.6 merge depends on sql_yacc.h

To make st_select_lex::master_unit() inlinable:
- moved it's definition to sql_lex.h
- removed base class virtual master_unit() declaration since this method is
  specific to st_select_lex

Overhead change:
st_select_lex::master_unit()      0.17% -> out of radar
execute_sqlcom_select()           0.13% -> 0.12%
JOIN::save_explain_data_intern()  0.27% -> 0.23%
JOIN::optimize_inner()            0.76% -> 0.72%
JOIN::exec_inner()                0.30% -> 0.24%
JOIN::prepare()                   0.30% -> 0.29%
JOIN::optimize()                  0.05% -> 0.05%

Moved THD::set_command() definition to sql_class.h so that it can be inlined.

Overhead change:
THD::set_command        0.05% -> out of radar

Moved THD::set_query() definition to sql_class.h so that it can be inlined.

Overhead change:
THD::set_query       0.07% -> out of radar

MDEV-8257 Erroneous "Impossible where" when mixing decimal comparison and LIKE