When adding a column or index that uses plugin-defined
sysvar-based options with CREATE ... LIKE the server
was using the current value of the sysvar, not the default one.
Because parse_option_list() function was used both in create
and open and it tried to guess when it's create (need to use
current sysvar value and add a new name=value pair to the list)
or open (need to use default, without extending the list).
Let's move the list extending functionality into a separate
function and call it explicitly when needed. Operations that
add new objects (CREATE, ALTER ... ADD) will extend the list,
other operations (ALTER, CREATE ... LIKE, open) will not.
The sys_var class has the deprecation_substitute member to mark the
deprecated variables. As it's set, the server produces warnings when
these variables are used. However, the plugin has no means to utilize
that functionality.
So, the PLUGIN_VAR_DEPRECATED flag is introduced to set the
deprecation_substitute with the empty string. A non-empty string can
make the warning more informative, but there's no nice way seen to
specify it, and not that needed at the moment.
Also fixes:
MDEV-25399 Assertion `name.length == strlen(name.str)' failed in Item_func_sp::make_send_field
Also fixes a problem that in this scenario:
SET NAMES binary;
SELECT 'some not well-formed utf8 string';
the auto-generated column name copied the binary string value directly
to the Item name, without checking utf8 well-formedness.
After this change auto-generated column names work as follows:
- Zero bytes 0x00 are copied to the name using HEX notation
- In case of "SET NAMES binary", all bytes sequences that do not make
well-formed utf8 characters are copied to the name using HEX notation.
This patch changes the main name of 3 byte character set from utf8 to
utf8mb3. New old_mode UTF8_IS_UTF8MB3 is added and set TRUE by default,
so that utf8 would mean utf8mb3. If not set, utf8 would mean utf8mb4.
CREATE TEMPORARY TABLE locks SE plugin 6 times. 5 of these locks are
released by the end of the statement. And only 1 acquired by
init_from_binary_frm_image() / plugin_lock() remains.
The lock removed in this patch was clearly redundant.
Part of MDEV-17805 - Remove InnoDB cache for temporary tables.
As it isn't used. This leaves a less clustered syntax
for a INSTALL IF EXISTS SONAME option which could be added later.
This option could be checking the existance of the soname rather than the
installed plugin name which the rest of the INSTALL IF NOT EXISTS
is focused around.`
Add INSTALL SONAME IF NOT EXISTS; syntax only, installing
duplicate SONAMES doesn't currently cause any errors or warnings.
UNINSTALL SONAME IF EXISTS was added.
Allow the installation / uninstallation of plugins without
doing checks for existence first.
