MDEV-29718 Fix spider detection of same data node server

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

storage/spider/mysql-test/spider/bugfix/r/mdev_26151.result

@@ -6,6 +6,9 @@ for child2
 for child3
 set @old_spider_bgs_mode= @@spider_bgs_mode;
 set session spider_bgs_mode=1;
+set spider_same_server_link=1;
+set @old_spider_same_server_link=@@global.spider_same_server_link;
+set global spider_same_server_link=1;
 CREATE SERVER $srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 create table td (a int, PRIMARY KEY (a));
 create table ts (a int, PRIMARY KEY (a)) ENGINE=Spider COMMENT='WRAPPER "mysql", srv "srv_mdev_26151",TABLE "td", casual_read "3"';
@@ -26,6 +29,7 @@ min(a)
 drop table td, ts;
 drop server srv_mdev_26151;
 set session spider_bgs_mode=@old_spider_bgs_mode;
+set global spider_same_server_link=@old_spider_same_server_link;
 for master_1
 for child2
 for child3

storage/spider/mysql-test/spider/bugfix/r/mdev_28739_simple.result

@@ -5,6 +5,7 @@ for master_1
 for child2
 for child3
 set global query_cache_type= on;
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 create table t2 (c int);

storage/spider/mysql-test/spider/bugfix/r/mdev_28856.result

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 # testing monitoring_*

storage/spider/mysql-test/spider/bugfix/r/mdev_28998.result

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER s FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 CREATE TABLE t1 (a INT);
 INSERT INTO t1 VALUES (1),(2);

storage/spider/mysql-test/spider/bugfix/r/mdev_29163.result

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER s FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 CREATE TABLE t1 (a INT);
 CREATE TABLE t2 (b INT);

storage/spider/mysql-test/spider/bugfix/r/mdev_29456.result

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 create table t1 (c int);

storage/spider/mysql-test/spider/bugfix/r/mdev_29963.result

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 CREATE TABLE t (a INT) ENGINE=Spider;

storage/spider/mysql-test/spider/bugfix/r/mdev_30014.result

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 create table t1 (c int);

storage/spider/mysql-test/spider/bugfix/r/mdev_30392.result

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 CREATE TABLE t1 (a INT);
 INSERT INTO t1 VALUES (1),(2);

storage/spider/mysql-test/spider/bugfix/r/mdev_31338.result

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 CREATE TABLE t (c BLOB) ENGINE=InnoDB;
 CREATE TABLE ts (c BLOB) ENGINE=Spider COMMENT='WRAPPER "mysql",srv "srv",TABLE "t"';

storage/spider/mysql-test/spider/bugfix/r/mdev_31524.result

@@ -5,6 +5,7 @@ for master_1
 for child2
 for child3
 SET @old_spider_read_only_mode = @@session.spider_read_only_mode;
+set spider_same_server_link=1;
 CREATE SERVER $srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 set session spider_read_only_mode = default;
 create table t2 (c int);

storage/spider/mysql-test/spider/bugfix/r/mdev_31645.result

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 CREATE TABLE t1 ( a bigint(20) NOT NULL, b bigint(20) DEFAULT 0, PRIMARY KEY (a));
 CREATE TABLE t2 ( a bigint(20) NOT NULL, b bigint(20) DEFAULT 0, PRIMARY KEY (a)) ENGINE=SPIDER COMMENT='srv "srv", WRAPPER "mysql", TABLE "t1"';

storage/spider/mysql-test/spider/bugfix/r/mdev_31996.result

 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 set session spider_delete_all_rows_type=0;

storage/spider/mysql-test/spider/bugfix/r/mdev_32986.result

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 create table t2 (c varchar(16));

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

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 create table t1 (c int);
 create table t2 (d int);

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

@@ -4,6 +4,7 @@
 for master_1
 for child2
 for child3
+set spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 create table t1 (c1 int);
 create table t2 (c2 int);

storage/spider/mysql-test/spider/bugfix/t/mdev_26151.test

@@ -14,6 +14,10 @@
 --let $srv=srv_mdev_26151
 set @old_spider_bgs_mode= @@spider_bgs_mode;
 set session spider_bgs_mode=1;
+set spider_same_server_link=1;
+set @old_spider_same_server_link=@@global.spider_same_server_link;
+set global spider_same_server_link=1;
+
 evalp CREATE SERVER $srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 
 # casual_read != 0 && casual_read != 1
@@ -42,6 +46,7 @@ drop table td, ts;
 
 eval drop server $srv;
 set session spider_bgs_mode=@old_spider_bgs_mode;
+set global spider_same_server_link=@old_spider_same_server_link;
 
 --disable_query_log
 --disable_result_log

storage/spider/mysql-test/spider/bugfix/t/mdev_28739_simple.test

@@ -12,6 +12,7 @@
 #set @@global.debug_dbug="d:t:i:o,mysqld.trace";
 
 set global query_cache_type= on;
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 create table t2 (c int);

storage/spider/mysql-test/spider/bugfix/t/mdev_28856.test

@@ -9,6 +9,7 @@
 
 # This test covers some table params under consideration for inclusion
 # in the engine-defined options to be implemented in MDEV-28856.
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 

storage/spider/mysql-test/spider/bugfix/t/mdev_28998.test

@@ -12,6 +12,7 @@ if (`select not(count(*)) from information_schema.system_variables where variabl
 --source ../../t/test_init.inc
 --enable_result_log
 --enable_query_log
+set spider_same_server_link=1;
 evalp CREATE SERVER s FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 
 CREATE TABLE t1 (a INT);

storage/spider/mysql-test/spider/bugfix/t/mdev_29163.test

@@ -6,6 +6,7 @@
 --source ../../t/test_init.inc
 --enable_result_log
 --enable_query_log
+set spider_same_server_link=1;
 evalp CREATE SERVER s FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 
 CREATE TABLE t1 (a INT);

storage/spider/mysql-test/spider/bugfix/t/mdev_29456.test

@@ -8,6 +8,7 @@
 --enable_result_log
 --enable_query_log
 
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 

storage/spider/mysql-test/spider/bugfix/t/mdev_29963.test

@@ -7,6 +7,7 @@
 --enable_result_log
 --enable_query_log
 
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 

storage/spider/mysql-test/spider/bugfix/t/mdev_30014.test

@@ -7,6 +7,7 @@
 --enable_result_log
 --enable_query_log
 
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 

storage/spider/mysql-test/spider/bugfix/t/mdev_30392.test

@@ -6,6 +6,7 @@
 --source ../../t/test_init.inc
 --enable_result_log
 --enable_query_log
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 
 CREATE TABLE t1 (a INT);

storage/spider/mysql-test/spider/bugfix/t/mdev_31338.test

@@ -9,6 +9,7 @@
 --enable_result_log
 --enable_query_log
 
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 CREATE TABLE t (c BLOB) ENGINE=InnoDB;
 CREATE TABLE ts (c BLOB) ENGINE=Spider COMMENT='WRAPPER "mysql",srv "srv",TABLE "t"';

storage/spider/mysql-test/spider/bugfix/t/mdev_31524.test

@@ -10,6 +10,7 @@
 
 --let $srv=srv_mdev_31524
 SET @old_spider_read_only_mode = @@session.spider_read_only_mode;
+set spider_same_server_link=1;
 evalp CREATE SERVER $srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 
 # when the user does not set var nor the table option, the default

storage/spider/mysql-test/spider/bugfix/t/mdev_31645.test

@@ -6,6 +6,7 @@
 --source ../../t/test_init.inc
 --enable_result_log
 --enable_query_log
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 
 CREATE TABLE t1 ( a bigint(20) NOT NULL, b bigint(20) DEFAULT 0, PRIMARY KEY (a));

storage/spider/mysql-test/spider/bugfix/t/mdev_31996.test

@@ -4,6 +4,7 @@
 --enable_result_log
 --enable_query_log
 
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 

storage/spider/mysql-test/spider/bugfix/t/mdev_32986.test

@@ -6,6 +6,7 @@
 --source ../../t/test_init.inc
 --enable_result_log
 --enable_query_log
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 

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

@@ -8,6 +8,7 @@
 --enable_result_log
 --enable_query_log
 
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 create table t1 (c int);
 create table t2 (d int);

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

@@ -6,6 +6,7 @@
 --source ../../t/test_init.inc
 --enable_result_log
 --enable_query_log
+set spider_same_server_link=1;
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 create table t1 (c1 int);
 create table t2 (c2 int);

storage/spider/spd_db_mysql.cc

@@ -1985,7 +1985,7 @@ int spider_db_mbase::connect(
 
     if (!spider_param_same_server_link(thd))
     {
-      if (!strcmp(tgt_host, my_localhost))
+      if (!strcmp(tgt_host, my_localhost) || !tgt_host || !tgt_host[0])
       {
         if (!strcmp(tgt_socket, *spd_mysqld_unix_port))
         {
@@ -1995,7 +1995,7 @@ int spider_db_mbase::connect(
           DBUG_RETURN(ER_SPIDER_SAME_SERVER_LINK_NUM);
         }
       } else if (!strcmp(tgt_host, "127.0.0.1") ||
-        !strcmp(tgt_host, glob_hostname))
+        !strcmp(tgt_host, glob_hostname) || !tgt_host || !tgt_host[0])
       {
         if (tgt_port == (long) *spd_mysqld_port)
         {