MDEV-32753 Make spider init queries compatible with oracle sql mode

Remove ORACLE from the (session) sql_mode in connections made with sql
service to run init queries

The connection is new and the global variable value takes effect
rather than the session value from the caller of spider_db_init.

storage/spider/mysql-test/spider/bugfix/r/mdev_32753.result

+#
+# MDEV-32753 Spider engine does not load in ORACLE mode
+#
+select * from mysql.plugin;
+name	dl
+create table t (c int) Engine=SPIDER;
+drop table t;
+#
+# end of test mdev_32753
+#

storage/spider/mysql-test/spider/bugfix/r/mdev_32753_after_start.result

+#
+# MDEV-32753 Spider engine does not load in ORACLE mode
+#
+install soname 'ha_spider';
+select * from mysql.plugin;
+name	dl
+SPIDER	ha_spider.so
+SPIDER_ALLOC_MEM	ha_spider.so
+SPIDER_WRAPPER_PROTOCOLS	ha_spider.so
+create table t (c int) Engine=SPIDER;
+drop table t;
+#
+# end of test mdev_32753_after_start
+#

storage/spider/mysql-test/spider/bugfix/r/mdev_32753_after_start_session.result

+#
+# MDEV-32753 Spider engine does not load in ORACLE mode
+#
+set @old_sql_mode=@@sql_mode;
+SET @@sql_mode = CONCAT(@@sql_mode, ',ORACLE');
+install soname 'ha_spider';
+select * from mysql.plugin;
+name	dl
+SPIDER	ha_spider.so
+SPIDER_ALLOC_MEM	ha_spider.so
+SPIDER_WRAPPER_PROTOCOLS	ha_spider.so
+create table t (c int) Engine=SPIDER;
+drop table t;
+set sql_mode=@old_sql_mode;
+#
+# end of test mdev_32753_after_start
+#

storage/spider/mysql-test/spider/bugfix/t/mdev_32753.opt

+--sql-mode=oracle
+--plugin-load-add=ha_spider

storage/spider/mysql-test/spider/bugfix/t/mdev_32753.test

+--echo #
+--echo # MDEV-32753 Spider engine does not load in ORACLE mode
+--echo #
+
+# This test tests spider init during server startup under global
+# ORACLE mode
+select * from mysql.plugin;
+create table t (c int) Engine=SPIDER;
+drop table t;
+--echo #
+--echo # end of test mdev_32753
+--echo #

storage/spider/mysql-test/spider/bugfix/t/mdev_32753_after_start.opt

+--sql-mode=oracle

storage/spider/mysql-test/spider/bugfix/t/mdev_32753_after_start.test

+--echo #
+--echo # MDEV-32753 Spider engine does not load in ORACLE mode
+--echo #
+
+# This test tests spider init after startup under global ORACLE mode
+install soname 'ha_spider';
+select * from mysql.plugin;
+create table t (c int) Engine=SPIDER;
+drop table t;
+
+--disable_query_log
+--disable_result_log
+--source ../../include/clean_up_spider.inc
+--enable_result_log
+--enable_query_log
+
+--echo #
+--echo # end of test mdev_32753_after_start
+--echo #

storage/spider/mysql-test/spider/bugfix/t/mdev_32753_after_start_session.test

+--echo #
+--echo # MDEV-32753 Spider engine does not load in ORACLE mode
+--echo #
+
+# This test tests spider init after startup under session ORACLE mode
+set @old_sql_mode=@@sql_mode;
+SET @@sql_mode = CONCAT(@@sql_mode, ',ORACLE');
+install soname 'ha_spider';
+select * from mysql.plugin;
+create table t (c int) Engine=SPIDER;
+drop table t;
+set sql_mode=@old_sql_mode;
+
+--disable_query_log
+--disable_result_log
+--source ../../include/clean_up_spider.inc
+--enable_result_log
+--enable_query_log
+
+--echo #
+--echo # end of test mdev_32753_after_start
+--echo #

storage/spider/mysql-test/spider/include/clean_up_spider.inc

@@ -3,7 +3,7 @@ DROP FUNCTION spider_copy_tables;
 DROP FUNCTION spider_ping_table;
 DROP FUNCTION spider_bg_direct_sql;
 DROP FUNCTION spider_direct_sql;
-UNINSTALL SONAME IF EXISTS "ha_spider";
+UNINSTALL SONAME IF EXISTS 'ha_spider';
 DROP TABLE IF EXISTS mysql.spider_xa;
 DROP TABLE IF EXISTS mysql.spider_xa_member;
 DROP TABLE IF EXISTS mysql.spider_xa_failed_log;

storage/spider/spd_init_query.h

@@ -20,6 +20,9 @@
 */
 
 static LEX_STRING spider_init_queries[] = {
+  {C_STRING_WITH_LEN(
+    "SET @@SQL_MODE = REPLACE(@@SQL_MODE, 'ORACLE', '');"
+  )},
   {C_STRING_WITH_LEN(
     "create table if not exists mysql.spider_xa("
     "  format_id int not null default 0,"