MDEV-16288 ALTER TABLE…ALGORITHM=DEFAULT does not override alter_algorithm

- ALTER_ALGORITHM should be substituted when there is no mention of
algorithm in alter statement.
- Introduced algorithm(thd) in Alter_info. It returns the
user requested algorithm. If user doesn't specify algorithm explicitly then
it returns alter_algorithm variable.
- changed algorithm() to get_algorithm(thd) to return algorithm name for
displaying the error.
- set_requested_algorithm(algo_value) to avoid direct assignment on
requested_algorithm variable.
- Avoid direct access of requested_algorithm to encapsulate
requested_algorithm variable

7 files changed, 83 insertions, 22 deletions

diff --git a/mysql-test/suite/innodb/r/alter_algorithm,INPLACE.rdiff b/mysql-test/suite/innodb/r/alter_algorithm,INPLACE.rdiff
index 805ccdb563c..a176a9af29e 100644
--- a/mysql-test/suite/innodb/r/alter_algorithm,INPLACE.rdiff
+++ b/mysql-test/suite/innodb/r/alter_algorithm,INPLACE.rdiff
@@ -1,6 +1,6 @@
---- alter_algorithm.result
-+++ alter_algorithm.reject
-@@ -7,40 +7,40 @@
+--- alter_algorithm.result	2020-04-30 21:39:48.923115511 +0530
++++ alter_algorithm.reject	2020-04-30 21:45:04.131642093 +0530
+@@ -7,43 +7,43 @@
  INSERT INTO t1(f1, f2, f3) VALUES(1, 1, 1);
  SELECT @@alter_algorithm;
  @@alter_algorithm
@@ -55,10 +55,15 @@
 -info: Records: 1  Duplicates: 0  Warnings: 0
 +affected rows: 0
 +info: Records: 0  Duplicates: 0  Warnings: 0
+ ALTER TABLE t1 FORCE, ALGORITHM=DEFAULT;
+-affected rows: 1
+-info: Records: 1  Duplicates: 0  Warnings: 0
++affected rows: 0
++info: Records: 0  Duplicates: 0  Warnings: 0
  DROP TABLE t1;
  affected rows: 0
  CREATE TABLE t1(f1 INT PRIMARY KEY, f2 INT NOT NULL,
-@@ -53,22 +53,22 @@
+@@ -56,22 +56,22 @@
  FOREIGN KEY fidx(f1) REFERENCES t1(f1))ENGINE=INNODB;
  INSERT INTO t1(f1, f2, f4, f5) VALUES(1, 2, 3, 4);
  ALTER TABLE t1 ADD INDEX idx1(f4), page_compressed=1;
@@ -91,7 +96,7 @@
  DROP TABLE t2, t1;
  affected rows: 0
  CREATE TABLE t1(f1 INT NOT NULL,
-@@ -81,27 +81,27 @@
+@@ -84,28 +84,27 @@
  INSERT INTO t1(f1, f2) VALUES(1, 1);
  # Add column at the end of the table
  ALTER TABLE t1 ADD COLUMN f4 char(100) default 'BIG WALL';
@@ -119,7 +124,9 @@
 +info: Records: 0  Duplicates: 0  Warnings: 0
  # Rename table
  ALTER TABLE t1 RENAME t3;
- affected rows: 0
+-affected rows: 1
+-info: Records: 1  Duplicates: 0  Warnings: 0
++affected rows: 0
  # Drop Virtual Column
  ALTER TABLE t3 DROP COLUMN vcol;
 -affected rows: 1
@@ -129,7 +136,7 @@
  # Column length varies
  ALTER TABLE t2 CHANGE f3 f3 VARCHAR(20);
  affected rows: 0
-@@ -109,12 +109,12 @@
+@@ -113,12 +112,12 @@
  SET foreign_key_checks = 0;
  affected rows: 0
  ALTER TABLE t3 ADD FOREIGN KEY fidx(f2) REFERENCES t2(f1);
diff --git a/mysql-test/suite/innodb/r/alter_algorithm,INSTANT.rdiff b/mysql-test/suite/innodb/r/alter_algorithm,INSTANT.rdiff
index 6d2ee160e46..414b7dc8b0c 100644
--- a/mysql-test/suite/innodb/r/alter_algorithm,INSTANT.rdiff
+++ b/mysql-test/suite/innodb/r/alter_algorithm,INSTANT.rdiff
@@ -1,6 +1,6 @@
---- alter_algorithm.result
-+++ alter_algorithm.reject
-@@ -7,40 +7,32 @@
+--- alter_algorithm.result	2020-04-30 21:39:48.923115511 +0530
++++ alter_algorithm.reject	2020-04-30 21:47:08.245465018 +0530
+@@ -7,43 +7,35 @@
  INSERT INTO t1(f1, f2, f3) VALUES(1, 1, 1);
  SELECT @@alter_algorithm;
  @@alter_algorithm
@@ -47,10 +47,15 @@
 -affected rows: 1
 -info: Records: 1  Duplicates: 0  Warnings: 0
 +Got one of the listed errors
+ ALTER TABLE t1 FORCE, ALGORITHM=DEFAULT;
+-affected rows: 1
+-info: Records: 1  Duplicates: 0  Warnings: 0
++affected rows: 0
++info: Records: 0  Duplicates: 0  Warnings: 0
  DROP TABLE t1;
  affected rows: 0
  CREATE TABLE t1(f1 INT PRIMARY KEY, f2 INT NOT NULL,
-@@ -53,22 +45,17 @@
+@@ -56,22 +48,17 @@
  FOREIGN KEY fidx(f1) REFERENCES t1(f1))ENGINE=INNODB;
  INSERT INTO t1(f1, f2, f4, f5) VALUES(1, 2, 3, 4);
  ALTER TABLE t1 ADD INDEX idx1(f4), page_compressed=1;
@@ -78,7 +83,7 @@
  DROP TABLE t2, t1;
  affected rows: 0
  CREATE TABLE t1(f1 INT NOT NULL,
-@@ -81,27 +68,27 @@
+@@ -84,28 +71,27 @@
  INSERT INTO t1(f1, f2) VALUES(1, 1);
  # Add column at the end of the table
  ALTER TABLE t1 ADD COLUMN f4 char(100) default 'BIG WALL';
@@ -106,7 +111,9 @@
 +info: Records: 0  Duplicates: 0  Warnings: 0
  # Rename table
  ALTER TABLE t1 RENAME t3;
- affected rows: 0
+-affected rows: 1
+-info: Records: 1  Duplicates: 0  Warnings: 0
++affected rows: 0
  # Drop Virtual Column
  ALTER TABLE t3 DROP COLUMN vcol;
 -affected rows: 1
@@ -116,7 +123,7 @@
  # Column length varies
  ALTER TABLE t2 CHANGE f3 f3 VARCHAR(20);
  affected rows: 0
-@@ -109,12 +96,12 @@
+@@ -113,12 +99,12 @@
  SET foreign_key_checks = 0;
  affected rows: 0
  ALTER TABLE t3 ADD FOREIGN KEY fidx(f2) REFERENCES t2(f1);
diff --git a/mysql-test/suite/innodb/r/alter_algorithm,NOCOPY.rdiff b/mysql-test/suite/innodb/r/alter_algorithm,NOCOPY.rdiff
index c6ce83b5d9f..2aa8c72265a 100644
--- a/mysql-test/suite/innodb/r/alter_algorithm,NOCOPY.rdiff
+++ b/mysql-test/suite/innodb/r/alter_algorithm,NOCOPY.rdiff
@@ -1,6 +1,6 @@
---- alter_algorithm.result
-+++ alter_algorithm.reject
-@@ -7,40 +7,32 @@
+--- alter_algorithm.result	2020-04-30 21:39:48.923115511 +0530
++++ alter_algorithm.reject	2020-04-30 21:52:10.785967739 +0530
+@@ -7,43 +7,35 @@
  INSERT INTO t1(f1, f2, f3) VALUES(1, 1, 1);
  SELECT @@alter_algorithm;
  @@alter_algorithm
@@ -47,10 +47,15 @@
 -affected rows: 1
 -info: Records: 1  Duplicates: 0  Warnings: 0
 +Got one of the listed errors
+ ALTER TABLE t1 FORCE, ALGORITHM=DEFAULT;
+-affected rows: 1
+-info: Records: 1  Duplicates: 0  Warnings: 0
++affected rows: 0
++info: Records: 0  Duplicates: 0  Warnings: 0
  DROP TABLE t1;
  affected rows: 0
  CREATE TABLE t1(f1 INT PRIMARY KEY, f2 INT NOT NULL,
-@@ -53,22 +45,22 @@
+@@ -56,22 +48,22 @@
  FOREIGN KEY fidx(f1) REFERENCES t1(f1))ENGINE=INNODB;
  INSERT INTO t1(f1, f2, f4, f5) VALUES(1, 2, 3, 4);
  ALTER TABLE t1 ADD INDEX idx1(f4), page_compressed=1;
@@ -83,7 +88,7 @@
  DROP TABLE t2, t1;
  affected rows: 0
  CREATE TABLE t1(f1 INT NOT NULL,
-@@ -81,27 +73,27 @@
+@@ -84,28 +76,27 @@
  INSERT INTO t1(f1, f2) VALUES(1, 1);
  # Add column at the end of the table
  ALTER TABLE t1 ADD COLUMN f4 char(100) default 'BIG WALL';
@@ -111,7 +116,9 @@
 +info: Records: 0  Duplicates: 0  Warnings: 0
  # Rename table
  ALTER TABLE t1 RENAME t3;
- affected rows: 0
+-affected rows: 1
+-info: Records: 1  Duplicates: 0  Warnings: 0
++affected rows: 0
  # Drop Virtual Column
  ALTER TABLE t3 DROP COLUMN vcol;
 -affected rows: 1
@@ -121,7 +128,7 @@
  # Column length varies
  ALTER TABLE t2 CHANGE f3 f3 VARCHAR(20);
  affected rows: 0
-@@ -109,12 +101,12 @@
+@@ -113,12 +104,12 @@
  SET foreign_key_checks = 0;
  affected rows: 0
  ALTER TABLE t3 ADD FOREIGN KEY fidx(f2) REFERENCES t2(f1);
diff --git a/mysql-test/suite/innodb/r/alter_algorithm.result b/mysql-test/suite/innodb/r/alter_algorithm.result
index bcfbe3355f9..717d31de6a0 100644
--- a/mysql-test/suite/innodb/r/alter_algorithm.result
+++ b/mysql-test/suite/innodb/r/alter_algorithm.result
@@ -41,6 +41,9 @@ info: Records: 1  Duplicates: 0  Warnings: 0
 ALTER TABLE t1 ENGINE=INNODB;
 affected rows: 1
 info: Records: 1  Duplicates: 0  Warnings: 0
+ALTER TABLE t1 FORCE, ALGORITHM=DEFAULT;
+affected rows: 1
+info: Records: 1  Duplicates: 0  Warnings: 0
 DROP TABLE t1;
 affected rows: 0
 CREATE TABLE t1(f1 INT PRIMARY KEY, f2 INT NOT NULL,
@@ -97,7 +100,8 @@ affected rows: 1
 info: Records: 1  Duplicates: 0  Warnings: 0
 # Rename table
 ALTER TABLE t1 RENAME t3;
-affected rows: 0
+affected rows: 1
+info: Records: 1  Duplicates: 0  Warnings: 0
 # Drop Virtual Column
 ALTER TABLE t3 DROP COLUMN vcol;
 affected rows: 1
diff --git a/mysql-test/suite/innodb/r/alter_algorithm2.result b/mysql-test/suite/innodb/r/alter_algorithm2.result
index 1cea3f4cd43..350c1c51482 100644
--- a/mysql-test/suite/innodb/r/alter_algorithm2.result
+++ b/mysql-test/suite/innodb/r/alter_algorithm2.result
@@ -54,3 +54,23 @@ DROP PROCEDURE p1;
 affected rows: 0
 DROP PROCEDURE p2;
 affected rows: 0
+CREATE TABLE t1(id INT PRIMARY KEY,
+col1 INT UNSIGNED NOT NULL UNIQUE)ENGINE=InnoDB;
+affected rows: 0
+INSERT INTO t1 VALUES(1,1),(2,2),(3,3);
+affected rows: 3
+info: Records: 3  Duplicates: 0  Warnings: 0
+SET ALTER_ALGORITHM=INSTANT;
+affected rows: 0
+ALTER TABLE t1 DROP COLUMN col1;
+ERROR 0A000: ALGORITHM=INSTANT is not supported for this operation. Try ALGORITHM=INPLACE
+ALTER TABLE t1 DROP COLUMN col1, ALGORITHM=NOCOPY;
+ERROR 0A000: ALGORITHM=NOCOPY is not supported for this operation. Try ALGORITHM=INPLACE
+ALTER TABLE t1 DROP COLUMN col1, ALGORITHM=DEFAULT;
+affected rows: 0
+info: Records: 0  Duplicates: 0  Warnings: 0
+ALTER TABLE t1 DROP PRIMARY KEY, ALGORITHM=DEFAULT;
+affected rows: 3
+info: Records: 3  Duplicates: 0  Warnings: 0
+DROP TABLE t1;
+affected rows: 0
diff --git a/mysql-test/suite/innodb/t/alter_algorithm.test b/mysql-test/suite/innodb/t/alter_algorithm.test
index d410a15154d..08c23b505f3 100644
--- a/mysql-test/suite/innodb/t/alter_algorithm.test
+++ b/mysql-test/suite/innodb/t/alter_algorithm.test
@@ -55,6 +55,10 @@ ALTER TABLE t1 ROW_FORMAT=COMPRESSED;
 --error $error_code
 ALTER TABLE t1 ENGINE=INNODB;
 
+# Irrespective of alter_algorithm value, the following command
+# should succeed because of explicitly mentioning ALGORTHM=DEFAULT
+ALTER TABLE t1 FORCE, ALGORITHM=DEFAULT;
+
 DROP TABLE t1;
 --disable_info
 
diff --git a/mysql-test/suite/innodb/t/alter_algorithm2.test b/mysql-test/suite/innodb/t/alter_algorithm2.test
index 02b49c797bc..cf538e30196 100644
--- a/mysql-test/suite/innodb/t/alter_algorithm2.test
+++ b/mysql-test/suite/innodb/t/alter_algorithm2.test
@@ -44,4 +44,16 @@ call p1();
 DROP TABLE t1;
 DROP PROCEDURE p1;
 DROP PROCEDURE p2;
+
+CREATE TABLE t1(id INT PRIMARY KEY,
+	        col1 INT UNSIGNED NOT NULL UNIQUE)ENGINE=InnoDB;
+INSERT INTO t1 VALUES(1,1),(2,2),(3,3);
+SET ALTER_ALGORITHM=INSTANT;
+--error ER_ALTER_OPERATION_NOT_SUPPORTED
+ALTER TABLE t1 DROP COLUMN col1;
+--error ER_ALTER_OPERATION_NOT_SUPPORTED
+ALTER TABLE t1 DROP COLUMN col1, ALGORITHM=NOCOPY;
+ALTER TABLE t1 DROP COLUMN col1, ALGORITHM=DEFAULT;
+ALTER TABLE t1 DROP PRIMARY KEY, ALGORITHM=DEFAULT;
+DROP TABLE t1;
 --disable_info