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

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- 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
This commit is contained in:
Thirunarayanan Balathandayuthapani
2020-04-25 14:27:00 +05:30
parent f98017bb6d
commit ec9908b257
13 changed files with 143 additions and 50 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
mysql-test/suite/innodb/r/alter_algorithm,INPLACE.rdiff
View File

@ -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
@ -54,11 +54,16 @@
-affected rows: 1
-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);

21
mysql-test/suite/innodb/r/alter_algorithm,INSTANT.rdiff
View File

@ -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);

21
mysql-test/suite/innodb/r/alter_algorithm,NOCOPY.rdiff
View File

@ -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);

6
mysql-test/suite/innodb/r/alter_algorithm.result
View File

@ -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

20
mysql-test/suite/innodb/r/alter_algorithm2.result
View File

@ -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

4
mysql-test/suite/innodb/t/alter_algorithm.test
View File

@ -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

12
mysql-test/suite/innodb/t/alter_algorithm2.test
View File

@ -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

34
sql/sql_alter.cc
View File

@ -69,6 +69,10 @@ bool Alter_info::set_requested_algorithm(const LEX_CSTRING *str)
return false;
}
void Alter_info::set_requested_algorithm(enum_alter_table_algorithm algo_val)
{
requested_algorithm= algo_val;
}
bool Alter_info::set_requested_lock(const LEX_CSTRING *str)
{
@ -86,13 +90,16 @@ bool Alter_info::set_requested_lock(const LEX_CSTRING *str)
return false;
}
const char* Alter_info::algorithm() const
const char* Alter_info::algorithm_clause(THD *thd) const
{
switch (requested_algorithm) {
switch (algorithm(thd)) {
case ALTER_TABLE_ALGORITHM_INPLACE:
return "ALGORITHM=INPLACE";
case ALTER_TABLE_ALGORITHM_COPY:
return "ALGORITHM=COPY";
case ALTER_TABLE_ALGORITHM_NONE:
DBUG_ASSERT(0);
/* Fall through */
case ALTER_TABLE_ALGORITHM_DEFAULT:
return "ALGORITHM=DEFAULT";
case ALTER_TABLE_ALGORITHM_NOCOPY:
@ -123,9 +130,6 @@ const char* Alter_info::lock() const
bool Alter_info::supports_algorithm(THD *thd, enum_alter_inplace_result result,
const Alter_inplace_info *ha_alter_info)
{
if (requested_algorithm == Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT)
requested_algorithm = (Alter_info::enum_alter_table_algorithm) thd->variables.alter_algorithm;
switch (result) {
case HA_ALTER_INPLACE_EXCLUSIVE_LOCK:
case HA_ALTER_INPLACE_SHARED_LOCK:
@ -134,16 +138,16 @@ bool Alter_info::supports_algorithm(THD *thd, enum_alter_inplace_result result,
return false;
case HA_ALTER_INPLACE_COPY_NO_LOCK:
case HA_ALTER_INPLACE_COPY_LOCK:
if (requested_algorithm >= Alter_info::ALTER_TABLE_ALGORITHM_NOCOPY)
if (algorithm(thd) >= Alter_info::ALTER_TABLE_ALGORITHM_NOCOPY)
{
ha_alter_info->report_unsupported_error(algorithm(),
ha_alter_info->report_unsupported_error(algorithm_clause(thd),
"ALGORITHM=INPLACE");
return true;
}
return false;
case HA_ALTER_INPLACE_NOCOPY_NO_LOCK:
case HA_ALTER_INPLACE_NOCOPY_LOCK:
if (requested_algorithm == Alter_info::ALTER_TABLE_ALGORITHM_INSTANT)
if (algorithm(thd) == Alter_info::ALTER_TABLE_ALGORITHM_INSTANT)
{
ha_alter_info->report_unsupported_error("ALGORITHM=INSTANT",
"ALGORITHM=NOCOPY");
@ -151,9 +155,9 @@ bool Alter_info::supports_algorithm(THD *thd, enum_alter_inplace_result result,
}
return false;
case HA_ALTER_INPLACE_NOT_SUPPORTED:
if (requested_algorithm >= Alter_info::ALTER_TABLE_ALGORITHM_INPLACE)
if (algorithm(thd) >= Alter_info::ALTER_TABLE_ALGORITHM_INPLACE)
{
ha_alter_info->report_unsupported_error(algorithm(),
ha_alter_info->report_unsupported_error(algorithm_clause(thd),
"ALGORITHM=COPY");
return true;
}
@ -174,7 +178,7 @@ bool Alter_info::supports_lock(THD *thd, enum_alter_inplace_result result,
case HA_ALTER_INPLACE_EXCLUSIVE_LOCK:
// If SHARED lock and no particular algorithm was requested, use COPY.
if (requested_lock == Alter_info::ALTER_TABLE_LOCK_SHARED &&
requested_algorithm == Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT &&
algorithm(thd) == Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT &&
thd->variables.alter_algorithm ==
Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT)
return false;
@ -237,6 +241,14 @@ bool Alter_info::vers_prohibited(THD *thd) const
return false;
}
Alter_info::enum_alter_table_algorithm
Alter_info::algorithm(const THD *thd) const
{
if (requested_algorithm == ALTER_TABLE_ALGORITHM_NONE)
return (Alter_info::enum_alter_table_algorithm) thd->variables.alter_algorithm;
return requested_algorithm;
}
Alter_table_ctx::Alter_table_ctx()
: datetime_field(NULL), error_if_not_empty(false),

26
sql/sql_alter.h
View File

@ -57,7 +57,10 @@ public:
ALTER_TABLE_ALGORITHM_NOCOPY,
// Instant should allow any operation that changes metadata only.
ALTER_TABLE_ALGORITHM_INSTANT
ALTER_TABLE_ALGORITHM_INSTANT,
// When there is no specification of algorithm during alter table.
ALTER_TABLE_ALGORITHM_NONE
};
@ -104,8 +107,11 @@ public:
List<const char> partition_names;
// Number of partitions.
uint num_parts;
private:
// Type of ALTER TABLE algorithm.
enum_alter_table_algorithm requested_algorithm;
public:
// Type of ALTER TABLE lock.
enum_alter_table_lock requested_lock;
@ -114,7 +120,7 @@ public:
flags(0), partition_flags(0),
keys_onoff(LEAVE_AS_IS),
num_parts(0),
requested_algorithm(ALTER_TABLE_ALGORITHM_DEFAULT),
requested_algorithm(ALTER_TABLE_ALGORITHM_NONE),
requested_lock(ALTER_TABLE_LOCK_DEFAULT)
{}
@ -130,7 +136,7 @@ public:
keys_onoff= LEAVE_AS_IS;
num_parts= 0;
partition_names.empty();
requested_algorithm= ALTER_TABLE_ALGORITHM_DEFAULT;
requested_algorithm= ALTER_TABLE_ALGORITHM_NONE;
requested_lock= ALTER_TABLE_LOCK_DEFAULT;
}
@ -177,10 +183,16 @@ public:
bool set_requested_lock(const LEX_CSTRING *str);
/**
Set the requested algorithm to the given algorithm value
@param algo_value algorithm to be set
*/
void set_requested_algorithm(enum_alter_table_algorithm algo_value);
/**
Returns the algorithm value in the format "algorithm=value"
*/
const char* algorithm() const;
const char* algorithm_clause(THD *thd) const;
/**
Returns the lock value in the format "lock=value"
@ -216,6 +228,12 @@ public:
bool supports_lock(THD *thd, enum_alter_inplace_result result,
const Alter_inplace_info *ha_alter_info);
/**
Return user requested algorithm. If user does not specify
algorithm then return alter_algorithm variable value.
*/
enum_alter_table_algorithm algorithm(const THD *thd) const;
private:
Alter_info &operator=(const Alter_info &rhs); // not implemented
Alter_info(const Alter_info &rhs); // not implemented

2
sql/sql_partition.cc
View File

@ -6008,7 +6008,7 @@ the generated partition syntax in a correct manner.
*/
if (alter_info->partition_flags != ALTER_PARTITION_INFO ||
!table->part_info ||
alter_info->requested_algorithm !=
alter_info->algorithm(thd) !=
Alter_info::ALTER_TABLE_ALGORITHM_INPLACE ||
!table->part_info->has_same_partitioning(part_info))
{

18
sql/sql_table.cc
View File

@ -9558,7 +9558,7 @@ do_continue:;
*/
if (!(alter_info->flags & ~(ALTER_RENAME | ALTER_KEYS_ONOFF)) &&
alter_info->partition_flags == 0 &&
alter_info->requested_algorithm !=
alter_info->algorithm(thd) !=
Alter_info::ALTER_TABLE_ALGORITHM_COPY) // No need to touch frm.
{
bool res;
@ -9636,7 +9636,7 @@ do_continue:;
"LOCK=DEFAULT");
DBUG_RETURN(true);
}
else if (alter_info->requested_algorithm !=
else if (alter_info->algorithm(thd) !=
Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT)
{
my_error(ER_ALTER_OPERATION_NOT_SUPPORTED_REASON, MYF(0),
@ -9676,20 +9676,21 @@ do_continue:;
using in-place API.
*/
if ((thd->variables.alter_algorithm == Alter_info::ALTER_TABLE_ALGORITHM_COPY &&
alter_info->requested_algorithm !=
alter_info->algorithm(thd) !=
Alter_info::ALTER_TABLE_ALGORITHM_INPLACE)
|| is_inplace_alter_impossible(table, create_info, alter_info)
|| IF_PARTITIONING((partition_changed &&
!(table->s->db_type()->partition_flags() & HA_USE_AUTO_PARTITION)), 0))
{
if (alter_info->requested_algorithm ==
if (alter_info->algorithm(thd) ==
Alter_info::ALTER_TABLE_ALGORITHM_INPLACE)
{
my_error(ER_ALTER_OPERATION_NOT_SUPPORTED, MYF(0),
"ALGORITHM=INPLACE", "ALGORITHM=COPY");
DBUG_RETURN(true);
}
alter_info->requested_algorithm= Alter_info::ALTER_TABLE_ALGORITHM_COPY;
alter_info->set_requested_algorithm(
Alter_info::ALTER_TABLE_ALGORITHM_COPY);
}
/*
@ -9809,7 +9810,7 @@ do_continue:;
/* Remember that we have not created table in storage engine yet. */
bool no_ha_table= true;
if (alter_info->requested_algorithm != Alter_info::ALTER_TABLE_ALGORITHM_COPY)
if (alter_info->algorithm(thd) != Alter_info::ALTER_TABLE_ALGORITHM_COPY)
{
Alter_inplace_info ha_alter_info(create_info, alter_info,
key_info, key_count,
@ -9900,7 +9901,7 @@ do_continue:;
// If SHARED lock and no particular algorithm was requested, use COPY.
if (inplace_supported == HA_ALTER_INPLACE_EXCLUSIVE_LOCK &&
alter_info->requested_lock == Alter_info::ALTER_TABLE_LOCK_SHARED &&
alter_info->requested_algorithm ==
alter_info->algorithm(thd) ==
Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT &&
thd->variables.alter_algorithm ==
Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT)
@ -10743,7 +10744,8 @@ bool mysql_recreate_table(THD *thd, TABLE_LIST *table_list, bool table_copy)
alter_info.flags= (ALTER_CHANGE_COLUMN | ALTER_RECREATE);
if (table_copy)
alter_info.requested_algorithm= Alter_info::ALTER_TABLE_ALGORITHM_COPY;
alter_info.set_requested_algorithm(
Alter_info::ALTER_TABLE_ALGORITHM_COPY);
bool res= mysql_alter_table(thd, &null_clex_str, &null_clex_str, &create_info,
table_list, &alter_info, 0,

4
sql/sql_yacc.yy
View File

@ -8531,8 +8531,8 @@ opt_index_lock_algorithm:
alter_algorithm_option:
ALGORITHM_SYM opt_equal DEFAULT
{
Lex->alter_info.requested_algorithm=
Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT;
Lex->alter_info.set_requested_algorithm(
Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT);
}
| ALGORITHM_SYM opt_equal ident
{

4
sql/sql_yacc_ora.yy
View File

@ -8468,8 +8468,8 @@ opt_index_lock_algorithm:
alter_algorithm_option:
ALGORITHM_SYM opt_equal DEFAULT
{
Lex->alter_info.requested_algorithm=
Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT;
Lex->alter_info.set_requested_algorithm(
Alter_info::ALTER_TABLE_ALGORITHM_DEFAULT);
}
| ALGORITHM_SYM opt_equal ident
{