MDEV-33087 ALTER TABLE...ALGORITHM=COPY should build indexes more efficiently

- Remove the usage of alter_algorithm variable and disable
the persistent statistics in alter_copy_bulk test case.

mysql-test/suite/innodb/r/alter_copy_bulk,OFF.rdiff

 --- bulk_copy_alter.result
 +++ bulk_copy_alter,non_bulk_alter_copy.result
-@@ -5,7 +5,7 @@
+@@ -6,7 +6,7 @@
  INSERT INTO t1 SELECT repeat('b', 200), seq FROM seq_3_to_65536;
- ALTER TABLE t1 ADD INDEX(f2);
- ALTER TABLE t1 ADD PRIMARY KEY(f1(2));
+ ALTER TABLE t1 ALGORITHM=COPY, ADD INDEX(f2);
+ ALTER TABLE t1 ALGORITHM=COPY, ADD PRIMARY KEY(f1(2));
 -ERROR 23000: Duplicate entry 'bb' for key 'PRIMARY'
 +ERROR 23000: Duplicate entry 'aa' for key 'PRIMARY'
  INSERT INTO t1 VALUES(repeat('a', 200), 1);

mysql-test/suite/innodb/r/alter_copy_bulk.result

-SET @@alter_algorithm=COPY;
+SET @default_stats_persistent= @@global.innodb_stats_persistent;
+SET GLOBAL innodb_stats_persistent= 0;
 CREATE TABLE t1(f1 CHAR(200), f2 INT NOT NULL)engine=InnoDB;
 INSERT INTO t1 SELECT repeat('a', 200), seq FROM seq_1_to_2;
-ALTER TABLE t1 FORCE;
+ALTER TABLE t1 ALGORITHM=COPY, FORCE;
 INSERT INTO t1 SELECT repeat('b', 200), seq FROM seq_3_to_65536;
-ALTER TABLE t1 ADD INDEX(f2);
-ALTER TABLE t1 ADD PRIMARY KEY(f1(2));
+ALTER TABLE t1 ALGORITHM=COPY, ADD INDEX(f2);
+ALTER TABLE t1 ALGORITHM=COPY, ADD PRIMARY KEY(f1(2));
 ERROR 23000: Duplicate entry 'bb' for key 'PRIMARY'
 INSERT INTO t1 VALUES(repeat('a', 200), 1);
 ALTER TABLE t1 ADD UNIQUE KEY(f2);
@@ -13,14 +14,14 @@ ALTER IGNORE TABLE t1 MODIFY f1 CHAR(200) NOT NULL;
 CREATE TABLE t2(f1 INT NOT NULL,
 FOREIGN KEY(f1) REFERENCES t1(f2))ENGINE=InnoDB;
 INSERT INTO t2 VALUES(1);
-ALTER TABLE t2 FORCE;
+ALTER TABLE t2 ALGORITHM=COPY, FORCE;
 DROP TABLE t2, t1;
 CREATE TABLE t1 (f1 INT, f2 INT) ENGINE=InnoDB PARTITION BY HASH(f1) PARTITIONS 2;
 INSERT INTO t1 VALUES(1, 1);
 INSERT INTO t1 SELECT seq, seq * 2 FROM seq_1_to_2;
-ALTER TABLE t1 FORCE;
+ALTER TABLE t1 ALGORITHM=COPY, FORCE;
 INSERT INTO t1 SELECT seq, seq * 2 FROM seq_3_to_65536;
-ALTER TABLE t1 ADD INDEX(f2);
+ALTER TABLE t1 ALGORITHM=COPY, ADD INDEX(f2);
 DROP TABLE t1;
 #
 # MDEV-34756 Validation of new foreign key skipped
@@ -39,13 +40,14 @@ ALTER TABLE t2 ADD CONSTRAINT FOREIGN KEY(f2) REFERENCES t1(f1);
 ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (`test`.`#sql-alter`, CONSTRAINT `#sql-alter_ibfk_2` FOREIGN KEY (`f2`) REFERENCES `t1` (`f1`))
 INSERT INTO t1 VALUES(3, 1);
 SET STATEMENT foreign_key_checks=0 FOR
-ALTER TABLE t2 ADD CONSTRAINT FOREIGN KEY(f2) REFERENCES t1(f1);
+ALTER TABLE t2 ALGORITHM=COPY, ADD CONSTRAINT FOREIGN KEY(f2) REFERENCES t1(f1);
 affected rows: 1
 info: Records: 1  Duplicates: 0  Warnings: 0
-ALTER TABLE t1 FORCE;
+ALTER TABLE t1 ALGORITHM=COPY, FORCE;
 affected rows: 2
 info: Records: 2  Duplicates: 0  Warnings: 0
-ALTER TABLE t2 FORCE;
+ALTER TABLE t2 ALGORITHM=COPY, FORCE;
 affected rows: 1
 info: Records: 1  Duplicates: 0  Warnings: 0
 DROP TABLE t2, t1;
+SET GLOBAL innodb_stats_persistent=@default_stats_persistent;

mysql-test/suite/innodb/t/alter_copy_bulk.test

 --source include/have_innodb.inc
 --source include/have_partition.inc
 --source include/have_sequence.inc
-SET @@alter_algorithm=COPY;
 
+SET @default_stats_persistent= @@global.innodb_stats_persistent;
+SET GLOBAL innodb_stats_persistent= 0;
 CREATE TABLE t1(f1 CHAR(200), f2 INT NOT NULL)engine=InnoDB;
 INSERT INTO t1 SELECT repeat('a', 200), seq FROM seq_1_to_2;
 # Buffer fits in the memory
-ALTER TABLE t1 FORCE;
+ALTER TABLE t1 ALGORITHM=COPY, FORCE;
 
 # Insert more entries
 INSERT INTO t1 SELECT repeat('b', 200), seq FROM seq_3_to_65536;
 # Alter should use temporary file for sorting
-ALTER TABLE t1 ADD INDEX(f2);
+ALTER TABLE t1 ALGORITHM=COPY, ADD INDEX(f2);
 
 # Error while buffering the insert operation
 --error ER_DUP_ENTRY
-ALTER TABLE t1 ADD PRIMARY KEY(f1(2));
+ALTER TABLE t1 ALGORITHM=COPY, ADD PRIMARY KEY(f1(2));
 
 INSERT INTO t1 VALUES(repeat('a', 200), 1);
 # Error while applying the bulk insert operation
@@ -29,18 +30,18 @@ CREATE TABLE t2(f1 INT NOT NULL,
 		FOREIGN KEY(f1) REFERENCES t1(f2))ENGINE=InnoDB;
 INSERT INTO t2 VALUES(1);
 # Bulk operation shouldn't happen because of foreign key constraints
-ALTER TABLE t2 FORCE;
+ALTER TABLE t2 ALGORITHM=COPY, FORCE;
 DROP TABLE t2, t1;
 
 CREATE TABLE t1 (f1 INT, f2 INT) ENGINE=InnoDB PARTITION BY HASH(f1) PARTITIONS 2;
 INSERT INTO t1 VALUES(1, 1);
 INSERT INTO t1 SELECT seq, seq * 2 FROM seq_1_to_2;
 # Buffer fits in the memory
-ALTER TABLE t1 FORCE;
+ALTER TABLE t1 ALGORITHM=COPY, FORCE;
 # Insert more entries
 INSERT INTO t1 SELECT seq, seq * 2 FROM seq_3_to_65536;
 # Alter should use temporary file for sorting
-ALTER TABLE t1 ADD INDEX(f2);
+ALTER TABLE t1 ALGORITHM=COPY, ADD INDEX(f2);
 DROP TABLE t1;
 
 --echo #
@@ -62,8 +63,9 @@ ALTER TABLE t2 ADD CONSTRAINT FOREIGN KEY(f2) REFERENCES t1(f1);
 INSERT INTO t1 VALUES(3, 1);
 --enable_info
 SET STATEMENT foreign_key_checks=0 FOR
-ALTER TABLE t2 ADD CONSTRAINT FOREIGN KEY(f2) REFERENCES t1(f1);
-ALTER TABLE t1 FORCE;
-ALTER TABLE t2 FORCE;
+ALTER TABLE t2 ALGORITHM=COPY, ADD CONSTRAINT FOREIGN KEY(f2) REFERENCES t1(f1);
+ALTER TABLE t1 ALGORITHM=COPY, FORCE;
+ALTER TABLE t2 ALGORITHM=COPY, FORCE;
 --disable_info
 DROP TABLE t2, t1;
+SET GLOBAL innodb_stats_persistent=@default_stats_persistent;