This issue has nothing to do with spider, as spider is simply using
the warning API provided by the server layer.

What happens is the value of THD::abort_on_warning during table
creation at the server layer. When it is true, warnings are converted
to errors, and if the first warning happens before the first error,
then the warning will "mask" errors.

When one executes a CREATE TABLE without table structure, i.e. without
defining columns of the table like in the case in the previous
comment, this causes create_table_mode to be
C_ASSISTED_DISCOVERY (-3), which causes thd->abort_on_warning
to be true. Thus the warning becomes an error and no further error is
displayed.

When one executes a (more common) CREATE TABLE with table
structure e.g. CREATE TABLE ts1 (c int)..., the
create_table_mode is C_ORDINARY_CREATE (0), which causes
mysql_create_frm_image() to be called and sets
thd->abort_on_warning to false, and errors (if any) are printed
instead of warnings.

See the following example in
storage/spider/mysql-test/spider/feature/r/engine_defined_attributes.result:

# MDEV-27860 SIGSEGV in spider_parse_connect_info on CREATE TABLE

CREATE TABLE tbl_a (c INT) ENGINE=SPIDER COMMENT="TABLE 'unknown_table'"

PARTITION BY LIST COLUMNS (c) (

PARTITION p DEFAULT COMMENT="srv 'unknown_server'" ENGINE=SPIDER

);

ERROR HY000: The foreign server name you are trying to reference does not exist. Data source error:  unknown_server

So this is either intended behaviour or a server layer bug. I am
leaning towards the former.

IMHO this is a regression. Here are my reasons:
1. "COMMENT or CONNECTION strings have been deprecated" is a warning, and should ever only be warning-level message only.
It is a new warning introduced in MDEV-28861, which is turned into an error due to other existing server behavior.
2. Importantly, the error reported is not the correct reason for the failure. IOW, the actual reason is not the use of COMMENT but being unable to connect to the remote host. This may be confusing for users. Another example of a similar situation in #3 below.
3. It looks like most Spider-related error resolution is lost. We have the example above (ERROR 1429 masked), and another example (ERROR 12702):

INSTALL PLUGIN Spider SONAME 'ha_spider.so';

CREATE USER spider@localhost IDENTIFIED BY 'pwd';

GRANT ALL ON test.* TO spider@localhost;

CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "../socket.sock",DATABASE 'test',USER 'spider',PASSWORD 'pwd');

CREATE TABLE ts1 ENGINE=Spider COMMENT='WRAPPER "mysql",SERVER "srv",TABLE "t1"';

At the command line will produce:

11.4.0-opt>CREATE TABLE ts1 ENGINE=Spider COMMENT='WRAPPER "mysql",SERVER "srv",TABLE "t1"';

ERROR 138 (0A000): Spider table params in COMMENT or CONNECTION strings have been deprecated and will be removed in a future release. Please use table options instead.

Versus

11.3.0-opt>CREATE TABLE ts1 ENGINE=Spider COMMENT='WRAPPER "mysql",SERVER "srv",TABLE "t1"';

ERROR 12702 (HY000): Remote table 'test.t1' is not found

Is this case too the failure reason is not the ERROR 138 COMMENT/CONNECTION depreciation, and ERROR 12702 is the correct reason for failure.
4. Users are used to the old syntax. Handling multiple levels of errors (one of which is not necessary at this point in time) can be confusing and off-putting.

Hi holyfoot, ptal thanks

upstream/bb-11.4-mdev-32999 5a5f92bf44bf6963ea9e71630eaa64b28ed9f941

MDEV-32999 Spider: only warn of connection string deprecation when creating a table

This commit will be squashed into that of MDEV-28861 to push. See below for the squashed commit.

upstream/bb-11.4-mdev-28861 73e4e4feb085547108c8f682d7cc864b6734a4e7

MDEV-28861 Deprecate spider table options by comment/connection

Also deprecating table params not implemented in MDEV-28856.

ok to push.

Thanks for the review.

Roel: no problem. Can you test the squashed MDEV-28861 patch that contains the patch in this ticket? It is 73e4e4feb085547108c8f682d7cc864b6734a4e7 referred to in my previous comment.

Confirmed resolved nicely:
1. No more ERROR for COMMENT deprec.
2. Deprec. WARNING when COMMENT is used.
Thank you again ycp.

Thanks Roel, pushed 20741b92370ee48843d6101b6d6eaecab58ba41a to 11.4