diff --git a/mysql-test/r/alter_table.result b/mysql-test/r/alter_table.result
index f91e0b3bf60a..459ded4ae553 100644
--- a/mysql-test/r/alter_table.result
+++ b/mysql-test/r/alter_table.result
@@ -3683,3 +3683,106 @@ ERROR 22004: Invalid use of NULL value
 ALTER TABLE t2 MODIFY fld0 POINT NOT NULL;
 ERROR 22004: Invalid use of NULL value
 DROP TABLE t1, t2;
+#
+# BUG#26848813: INDEXED COLUMN CAN'T BE CHANGED FROM VARCHAR(15)
+#               TO VARCHAR(40) INSTANTANEOUSLY
+SET @orig_sql_mode= @@sql_mode;
+SET @orig_innodb_large_prefix= @@global.innodb_large_prefix;
+SET GLOBAL innodb_large_prefix= ON;
+Warnings:
+Warning	131	Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See http://dev.mysql.com/doc/refman/5.7/en/innodb-file-format.html
+# Tests where an error is reported under strict mode when the index
+# limit exceeds the maximum supported length by SE.
+CREATE TABLE t1 (fld1 VARCHAR(768), KEY(fld1)) CHARSET latin1 ENGINE =InnoDB
+ROW_FORMAT= COMPACT;
+ERROR 42000: Specified key was too long; max key length is 767 bytes
+CREATE TABLE t2 (fld1 VARCHAR(3073), KEY(fld1)) CHARSET latin1 ENGINE= InnoDB;
+ERROR 42000: Specified key was too long; max key length is 3072 bytes
+# Test with innodb prefix indexes where the index limit is 767 bytes
+CREATE TABLE t1 (fld1 VARCHAR(767), KEY(fld1)) CHARSET latin1 ENGINE=INNODB
+ROW_FORMAT=COMPACT;
+ALTER TABLE t1 MODIFY fld1 VARCHAR(768), ALGORITHM= INPLACE;
+ERROR 42000: Specified key was too long; max key length is 767 bytes
+ALTER TABLE t1 MODIFY fld1 VARCHAR(768), ALGORITHM= COPY;
+ERROR 42000: Specified key was too long; max key length is 767 bytes
+# Test with innodb prefix indexes where the index limit is 3072 bytes
+CREATE TABLE t2 (fld1 VARCHAR(3072), KEY(fld1)) CHARSET latin1 ENGINE=INNODB
+ROW_FORMAT=DYNAMIC;
+ALTER TABLE t2 MODIFY fld1 VARCHAR(3073), ALGORITHM= INPLACE;
+ERROR 42000: Specified key was too long; max key length is 3072 bytes
+ALTER TABLE t2 MODIFY fld1 VARCHAR(3073), ALGORITHM= COPY;
+ERROR 42000: Specified key was too long; max key length is 3072 bytes
+# Tests with innodb_large_prefix disabled and strict mode.
+SET GLOBAL innodb_large_prefix= OFF;
+Warnings:
+Warning	131	Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See http://dev.mysql.com/doc/refman/5.7/en/innodb-file-format.html
+CREATE TABLE t3 (fld1 VARCHAR(3072), KEY(fld1)) CHARSET latin1 ENGINE= InnoDB;
+ERROR 42000: Specified key was too long; max key length is 767 bytes
+DROP TABLE t1, t2;
+SET sql_mode= '';
+Warnings:
+Warning	3090	Changing sql mode 'NO_AUTO_CREATE_USER' is deprecated. It will be removed in a future release.
+SET GLOBAL innodb_large_prefix= ON;
+Warnings:
+Warning	131	Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See http://dev.mysql.com/doc/refman/5.7/en/innodb-file-format.html
+# Test where the indexes are truncated to fit the index limit and
+# a warning is reported under non-strict mode when the index exceeds
+# the SE limit.
+CREATE TABLE t1 (fld1 VARCHAR(768), KEY(fld1)) ENGINE= InnoDB
+ROW_FORMAT=COMPACT;
+Warnings:
+Warning	1071	Specified key was too long; max key length is 767 bytes
+CREATE TABLE t2 (fld1 VARCHAR(3073), KEY(fld1)) ENGINE= InnoDB;
+Warnings:
+Warning	1071	Specified key was too long; max key length is 3072 bytes
+# Test with innodb prefix indexes where the index limit is 767 bytes.
+CREATE TABLE t3 (fld1 VARCHAR(767), KEY(fld1))ENGINE=INNODB ROW_FORMAT=COMPACT;
+ALTER TABLE t3 MODIFY fld1 VARCHAR(768), ALGORITHM= INPLACE;
+Warnings:
+Warning	1071	Specified key was too long; max key length is 767 bytes
+ALTER TABLE t3 MODIFY fld1 VARCHAR(800), ALGORITHM= COPY;
+# Test with innodb prefix indexes where the index limit is 3072 bytes.
+CREATE TABLE t4 (fld1 VARCHAR(3072), KEY(fld1))ENGINE=INNODB
+ROW_FORMAT=DYNAMIC;
+ALTER TABLE t4 MODIFY fld1 VARCHAR(3073), ALGORITHM= INPLACE;
+Warnings:
+Warning	1071	Specified key was too long; max key length is 3072 bytes
+ALTER TABLE t4 MODIFY fld1 VARCHAR(3074), ALGORITHM= COPY;
+# For unique and primary keys, an error is reported even in non-strict
+# mode.
+CREATE TABLE t5(fld1 VARCHAR(768) PRIMARY KEY) ENGINE= InnoDB
+ROW_FORMAT=COMPACT;
+ERROR 42000: Specified key was too long; max key length is 767 bytes
+CREATE TABLE t5(fld1 VARCHAR(3073), UNIQUE KEY(fld1)) ENGINE= InnoDB;
+ERROR 42000: Specified key was too long; max key length is 3072 bytes
+# Tests with innodb_large_prefix disabled and strict mode.
+SET GLOBAL innodb_large_prefix= OFF;
+Warnings:
+Warning	131	Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See http://dev.mysql.com/doc/refman/5.7/en/innodb-file-format.html
+CREATE TABLE t5 (fld1 VARCHAR(3072), KEY(fld1)) CHARSET latin1 ENGINE= InnoDB;
+Warnings:
+Warning	1071	Specified key was too long; max key length is 767 bytes
+DROP TABLE t1, t2, t3, t4, t5;
+SET sql_mode= @orig_sql_mode;
+SET GLOBAL innodb_large_prefix= ON;
+# Tests added for coverage.
+CREATE TABLE t1(fld1 VARCHAR(3), KEY(fld1)) ENGINE=MYISAM;
+# Conversion of unpacked keys to packed keys reports
+# error for INPLACE Alter.
+ALTER TABLE t1 MODIFY fld1 VARCHAR(10), ALGORITHM=INPLACE;
+ERROR 0A000: ALGORITHM=INPLACE is not supported for this operation. Try ALGORITHM=COPY.
+# Succeeds with index rebuild.
+ALTER TABLE t1 MODIFY fld1 VARCHAR(10), ALGORITHM=COPY;
+# Succeeds since the row format is dynamic.
+CREATE TABLE t2(fld1 VARCHAR(768), KEY(fld1)) ENGINE= InnoDB ROW_FORMAT= DYNAMIC;
+# An error is reported when the index exceeds the column size
+# in both strict and non-strict mode.
+ALTER TABLE t2 ADD INDEX idx1(fld1(769));
+ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys
+SET sql_mode= '';
+ALTER TABLE t2 ADD INDEX idx1(fld1(769));
+ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys
+# Cleanup.
+DROP TABLE t1, t2;
+SET sql_mode= @orig_sql_mode;
+SET GLOBAL innodb_large_prefix= @orig_innodb_large_prefix;
diff --git a/mysql-test/r/innodb_mysql_sync.result b/mysql-test/r/innodb_mysql_sync.result
index 3a400e484f7c..960aec1a3d15 100644
--- a/mysql-test/r/innodb_mysql_sync.result
+++ b/mysql-test/r/innodb_mysql_sync.result
@@ -746,3 +746,22 @@ ALTER TABLE t1 MODIFY fld1 CHAR(20);
 #cleanup
 DROP TABLE t1;
 SET debug="-d,innodb_index_drop_count_zero";
+#
+# BUG#26848813: INDEXED COLUMN CAN'T BE CHANGED FROM VARCHAR(15)
+#               TO VARCHAR(40) INSTANTANEOUSLY
+CREATE TABLE t1(fld1 VARCHAR(5), KEY(fld1)) ENGINE= InnoDB;
+SET DEBUG="+d,innodb_index_drop_count_zero";
+# Without patch, an error is reported.
+ALTER TABLE t1 MODIFY fld1 VARCHAR(7), ALGORITHM= INPLACE;
+# Scenario where non-packed keys is converted to packed keys
+# before the patch, an error is reported.
+ALTER TABLE t1 MODIFY fld1 VARCHAR(9), ALGORITHM= INPLACE;
+SET DEBUG="-d,innodb_index_drop_count_zero";
+# Tests added for covering cases where rebuild is required.
+# Reducing the size of the field.
+ALTER TABLE t1 MODIFY fld1 VARCHAR(3), ALGORITHM= INPLACE;
+ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: Cannot change column type INPLACE. Try ALGORITHM=COPY.
+# Increasing the size of the field to boundary condition.
+ALTER TABLE t1 MODIFY fld1 VARCHAR(256), ALGORITHM= INPLACE;
+ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: Cannot change column type INPLACE. Try ALGORITHM=COPY.
+DROP TABLE t1;
diff --git a/mysql-test/suite/innodb/r/default_row_format_compatibility.result b/mysql-test/suite/innodb/r/default_row_format_compatibility.result
index e98b60a9f72d..72140352b00a 100644
--- a/mysql-test/suite/innodb/r/default_row_format_compatibility.result
+++ b/mysql-test/suite/innodb/r/default_row_format_compatibility.result
@@ -72,7 +72,7 @@ Table Name	Tablespace	Table Flags	Columns	Row Format	Zip Size	Space Type
 test/tab	test/tab	33	5	Dynamic	0	Single
 SET GLOBAL innodb_default_row_format=COMPACT;
 ALTER TABLE tab ROW_FORMAT=COMPACT;
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 DROP TABLE tab;
 SET GLOBAL innodb_default_row_format=Default;
 SELECT @@innodb_default_row_format;
diff --git a/mysql-test/suite/innodb/r/innodb-large-prefix.result b/mysql-test/suite/innodb/r/innodb-large-prefix.result
index f691d59f56f4..311c1742870a 100644
--- a/mysql-test/suite/innodb/r/innodb-large-prefix.result
+++ b/mysql-test/suite/innodb/r/innodb-large-prefix.result
@@ -5,14 +5,14 @@ CREATE TABLE t1(a int not null,key(a,a)) ENGINE=InnoDB DEFAULT CHARSET=latin1;
 ERROR 42S21: Duplicate column name 'a'
 CREATE TABLE t1(a int,b text,key(b(768))) ENGINE=InnoDB DEFAULT CHARSET=latin1
 ROW_FORMAT=COMPACT;
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 CREATE TABLE t1(a int not null,b text) ENGINE=InnoDB DEFAULT CHARSET=latin1
 ROW_FORMAT=COMPACT;
 INSERT INTO t1 VALUES (1,''),(2,''),(3,''),(4,''),(5,''),(6,''),(7,'');
 CREATE INDEX t1aa ON t1(a,a);
 ERROR 42S21: Duplicate column name 'a'
 CREATE INDEX t1b ON t1(b(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 SHOW CREATE TABLE t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
@@ -35,7 +35,7 @@ INSERT INTO t2 VALUES (1,''),(2,''),(3,''),(4,''),(5,''),(6,''),(7,'');
 CREATE INDEX t2aa ON t2(a,a);
 ERROR 42S21: Duplicate column name 'a'
 CREATE INDEX t2b ON t2(b(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 SELECT * FROM t2;
 a	b
 1	
diff --git a/mysql-test/suite/innodb/t/default_row_format_compatibility.test b/mysql-test/suite/innodb/t/default_row_format_compatibility.test
index 0fce0c4e5157..9753350fa27b 100644
--- a/mysql-test/suite/innodb/t/default_row_format_compatibility.test
+++ b/mysql-test/suite/innodb/t/default_row_format_compatibility.test
@@ -160,7 +160,7 @@ SELECT * FROM tab;
 SET GLOBAL innodb_default_row_format=COMPACT;
 
 # Check error ERROR 1709 (HY000): Index column size too large
--- error ER_INDEX_COLUMN_TOO_LONG
+--error ER_TOO_LONG_KEY
 ALTER TABLE tab ROW_FORMAT=COMPACT;
 
 # Cleanup
diff --git a/mysql-test/suite/innodb/t/innodb-large-prefix.test b/mysql-test/suite/innodb/t/innodb-large-prefix.test
index 57dc11002af0..b1e9b7c3cb5d 100644
--- a/mysql-test/suite/innodb/t/innodb-large-prefix.test
+++ b/mysql-test/suite/innodb/t/innodb-large-prefix.test
@@ -9,7 +9,7 @@
 
 --error ER_DUP_FIELDNAME
 CREATE TABLE t1(a int not null,key(a,a)) ENGINE=InnoDB DEFAULT CHARSET=latin1;
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 CREATE TABLE t1(a int,b text,key(b(768))) ENGINE=InnoDB DEFAULT CHARSET=latin1
 ROW_FORMAT=COMPACT;
 CREATE TABLE t1(a int not null,b text) ENGINE=InnoDB DEFAULT CHARSET=latin1
@@ -17,7 +17,7 @@ ROW_FORMAT=COMPACT;
 INSERT INTO t1 VALUES (1,''),(2,''),(3,''),(4,''),(5,''),(6,''),(7,'');
 --error ER_DUP_FIELDNAME
 CREATE INDEX t1aa ON t1(a,a);
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 CREATE INDEX t1b ON t1(b(768));
 SHOW CREATE TABLE t1;
 SELECT * FROM t1;
@@ -28,7 +28,7 @@ ROW_FORMAT=COMPACT;
 INSERT INTO t2 VALUES (1,''),(2,''),(3,''),(4,''),(5,''),(6,''),(7,'');
 --error ER_DUP_FIELDNAME
 CREATE INDEX t2aa ON t2(a,a);
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 CREATE INDEX t2b ON t2(b(768));
 SELECT * FROM t2;
 DROP TABLE t2;
diff --git a/mysql-test/suite/innodb_zip/r/index_large_prefix.result b/mysql-test/suite/innodb_zip/r/index_large_prefix.result
index 7f466e957f35..f4a43c413a01 100644
--- a/mysql-test/suite/innodb_zip/r/index_large_prefix.result
+++ b/mysql-test/suite/innodb_zip/r/index_large_prefix.result
@@ -494,11 +494,11 @@ drop table worklog5743;
 ### Test 6 ###
 create table worklog5743(a TEXT not null, primary key (a(1000)))
 row_format=compact;
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create table worklog5743(a TEXT)
 row_format=compact;
 create index idx on worklog5743(a(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create index idx on worklog5743(a(767));
 insert into worklog5743 values(repeat("a", 20000));
 begin;
@@ -546,12 +546,12 @@ drop table worklog5743;
 SET sql_mode= default;
 create table worklog5743(a TEXT not null) ROW_FORMAT=REDUNDANT;
 create index idx on worklog5743(a(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
 create table worklog5743(a TEXT not null) ROW_FORMAT=COMPACT;
 create index idx on worklog5743(a(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
 SET GLOBAL innodb_file_per_table=1;
diff --git a/mysql-test/suite/innodb_zip/r/index_large_prefix_4k.result b/mysql-test/suite/innodb_zip/r/index_large_prefix_4k.result
index 36d232f1e614..923e77892a7a 100644
--- a/mysql-test/suite/innodb_zip/r/index_large_prefix_4k.result
+++ b/mysql-test/suite/innodb_zip/r/index_large_prefix_4k.result
@@ -362,7 +362,7 @@ create table worklog5743(a TEXT not null, primary key (a(1000)));
 ERROR 42000: Specified key was too long; max key length is 768 bytes
 create table worklog5743(a TEXT) ROW_FORMAT=COMPACT;
 create index idx on worklog5743(a(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create index idx on worklog5743(a(767));
 insert into worklog5743 values(repeat("a", 20000));
 begin;
@@ -417,12 +417,12 @@ insert into worklog5743 values(repeat("a", 768));
 drop table worklog5743;
 create table worklog5743(a TEXT not null) ROW_FORMAT=REDUNDANT;
 create index idx on worklog5743(a(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
 create table worklog5743(a TEXT not null) ROW_FORMAT=COMPACT;
 create index idx on worklog5743(a(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
 SET GLOBAL innodb_file_per_table=1;
diff --git a/mysql-test/suite/innodb_zip/r/index_large_prefix_8k.result b/mysql-test/suite/innodb_zip/r/index_large_prefix_8k.result
index c9ee289123ee..f7eb850524a1 100644
--- a/mysql-test/suite/innodb_zip/r/index_large_prefix_8k.result
+++ b/mysql-test/suite/innodb_zip/r/index_large_prefix_8k.result
@@ -404,10 +404,10 @@ drop table worklog5743;
 ### Test 6 ###
 create table worklog5743(a TEXT not null, primary key (a(1000)))
 row_format=compact;
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create table worklog5743(a TEXT) row_format=compact;
 create index idx on worklog5743(a(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create index idx on worklog5743(a(767));
 insert into worklog5743 values(repeat("a", 20000));
 begin;
@@ -455,12 +455,12 @@ worklog5743	CREATE TABLE `worklog5743` (
 drop table worklog5743;
 create table worklog5743(a TEXT not null) ROW_FORMAT=REDUNDANT;
 create index idx on worklog5743(a(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
 create table worklog5743(a TEXT not null) ROW_FORMAT=COMPACT;
 create index idx on worklog5743(a(768));
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
 SET GLOBAL innodb_file_per_table=1;
diff --git a/mysql-test/suite/innodb_zip/r/prefix_index_liftedlimit.result b/mysql-test/suite/innodb_zip/r/prefix_index_liftedlimit.result
index fd2def62c494..fd9b2ac93c5e 100644
--- a/mysql-test/suite/innodb_zip/r/prefix_index_liftedlimit.result
+++ b/mysql-test/suite/innodb_zip/r/prefix_index_liftedlimit.result
@@ -30,9 +30,9 @@ col_1_varchar = REPEAT("c", 4000)
 0
 1
 ALTER TABLE worklog5743 ROW_FORMAT=REDUNDANT;
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 ALTER TABLE worklog5743 ROW_FORMAT=COMPACT;
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 ALTER TABLE worklog5743 ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=16;
 DROP TABLE worklog5743;
 CREATE TABLE worklog5743 (
diff --git a/mysql-test/suite/innodb_zip/r/wl6469.result b/mysql-test/suite/innodb_zip/r/wl6469.result
index ad328188efbd..1c64e20e23a5 100644
--- a/mysql-test/suite/innodb_zip/r/wl6469.result
+++ b/mysql-test/suite/innodb_zip/r/wl6469.result
@@ -270,8 +270,9 @@ SET sql_mode = default;
 set global innodb_large_prefix = 1;
 Warnings:
 Warning	131	Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See http://dev.mysql.com/doc/refman/5.7/en/innodb-file-format.html
-SET sql_mode='NO_ENGINE_SUBSTITUTION';
+SET sql_mode='NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES';
 Warnings:
+Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
 Warning	3090	Changing sql mode 'NO_AUTO_CREATE_USER' is deprecated. It will be removed in a future release.
 SET innodb_strict_mode=OFF;
 create temporary table t (
@@ -279,7 +280,7 @@ a int not null,
 b blob not null,
 index sk (b(3021))
 ) row_format = compact engine=innodb;
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create temporary table t (
 a int not null,
 b blob not null,
@@ -299,7 +300,7 @@ a int not null,
 b blob not null,
 index sk (b(3021))
 ) row_format = compact engine=innodb;
-ERROR HY000: Index column size too large. The maximum column size is 767 bytes.
+ERROR 42000: Specified key was too long; max key length is 767 bytes
 create temporary table t (
 a int not null,
 b blob not null,
diff --git a/mysql-test/suite/innodb_zip/t/index_large_prefix.test b/mysql-test/suite/innodb_zip/t/index_large_prefix.test
index 532ffc4b60e5..694eb69bdd77 100644
--- a/mysql-test/suite/innodb_zip/t/index_large_prefix.test
+++ b/mysql-test/suite/innodb_zip/t/index_large_prefix.test
@@ -370,7 +370,7 @@ drop table worklog5743;
 
 -- echo ### Test 6 ###
 # Create a table with old format, and the limit is 768 bytes.
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create table worklog5743(a TEXT not null, primary key (a(1000)))
 row_format=compact;
 
@@ -378,7 +378,7 @@ create table worklog5743(a TEXT)
 row_format=compact;
 
 # Excercise the column length check in ha_innobase::add_index()
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create index idx on worklog5743(a(768));
 
 # This should be successful
@@ -426,13 +426,13 @@ SET sql_mode= default;
 
 # We have a limit of 767 bytes for Antelope tables
 create table worklog5743(a TEXT not null) ROW_FORMAT=REDUNDANT;
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create index idx on worklog5743(a(768));
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
 
 create table worklog5743(a TEXT not null) ROW_FORMAT=COMPACT;
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create index idx on worklog5743(a(768));
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
diff --git a/mysql-test/suite/innodb_zip/t/index_large_prefix_4k.test b/mysql-test/suite/innodb_zip/t/index_large_prefix_4k.test
index a0229abc4f8f..0d4b86d6a4de 100644
--- a/mysql-test/suite/innodb_zip/t/index_large_prefix_4k.test
+++ b/mysql-test/suite/innodb_zip/t/index_large_prefix_4k.test
@@ -334,7 +334,7 @@ create table worklog5743(a TEXT not null, primary key (a(1000)));
 create table worklog5743(a TEXT) ROW_FORMAT=COMPACT;
 
 # Excercise the column length check in ha_innobase::add_index()
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create index idx on worklog5743(a(768));
 
 # This should be successful
@@ -385,13 +385,13 @@ drop table worklog5743;
 
 # We have a limit of 767 bytes for Antelope tables
 create table worklog5743(a TEXT not null) ROW_FORMAT=REDUNDANT;
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create index idx on worklog5743(a(768));
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
 
 create table worklog5743(a TEXT not null) ROW_FORMAT=COMPACT;
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create index idx on worklog5743(a(768));
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
diff --git a/mysql-test/suite/innodb_zip/t/index_large_prefix_8k.test b/mysql-test/suite/innodb_zip/t/index_large_prefix_8k.test
index 00a97249a957..c940915c01ca 100644
--- a/mysql-test/suite/innodb_zip/t/index_large_prefix_8k.test
+++ b/mysql-test/suite/innodb_zip/t/index_large_prefix_8k.test
@@ -360,14 +360,14 @@ drop table worklog5743;
 
 -- echo ### Test 6 ###
 # Create a table with old format, and the limit is 768 bytes.
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create table worklog5743(a TEXT not null, primary key (a(1000)))
 row_format=compact;
 
 create table worklog5743(a TEXT) row_format=compact;
 
 # Excercise the column length check in ha_innobase::add_index()
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create index idx on worklog5743(a(768));
 
 # This should be successful
@@ -414,13 +414,13 @@ drop table worklog5743;
 
 # We have a limit of 767 bytes for Antelope tables
 create table worklog5743(a TEXT not null) ROW_FORMAT=REDUNDANT;
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create index idx on worklog5743(a(768));
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
 
 create table worklog5743(a TEXT not null) ROW_FORMAT=COMPACT;
--- error ER_INDEX_COLUMN_TOO_LONG
+-- error ER_TOO_LONG_KEY
 create index idx on worklog5743(a(768));
 create index idx2 on worklog5743(a(767));
 drop table worklog5743;
diff --git a/mysql-test/suite/innodb_zip/t/prefix_index_liftedlimit.test b/mysql-test/suite/innodb_zip/t/prefix_index_liftedlimit.test
index dfc3777c58a0..9c21b7982984 100644
--- a/mysql-test/suite/innodb_zip/t/prefix_index_liftedlimit.test
+++ b/mysql-test/suite/innodb_zip/t/prefix_index_liftedlimit.test
@@ -47,9 +47,9 @@ WHERE col_1_varchar = REPEAT("c", 4000) AND col_2_varchar = REPEAT("o", 4000);
 INSERT INTO worklog5743 VALUES(REPEAT("a", 4000),REPEAT("o", 4000));
 DELETE FROM worklog5743 WHERE col_1_varchar = REPEAT("b", 4000);
 SELECT col_1_varchar = REPEAT("c", 4000) FROM worklog5743;
---error ER_INDEX_COLUMN_TOO_LONG
+--error ER_TOO_LONG_KEY
 ALTER TABLE worklog5743 ROW_FORMAT=REDUNDANT;
---error ER_INDEX_COLUMN_TOO_LONG
+--error ER_TOO_LONG_KEY
 ALTER TABLE worklog5743 ROW_FORMAT=COMPACT;
 ALTER TABLE worklog5743 ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=16;
 DROP TABLE worklog5743;
diff --git a/mysql-test/suite/innodb_zip/t/wl6469.test b/mysql-test/suite/innodb_zip/t/wl6469.test
index ebd5f727009f..1c49d3b1e775 100644
--- a/mysql-test/suite/innodb_zip/t/wl6469.test
+++ b/mysql-test/suite/innodb_zip/t/wl6469.test
@@ -219,10 +219,10 @@ SET sql_mode = default;
 #
 set global innodb_large_prefix = 1;
 #
-SET sql_mode='NO_ENGINE_SUBSTITUTION';
+SET sql_mode='NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES';
 SET innodb_strict_mode=OFF;
 --disable_warnings
---error ER_INDEX_COLUMN_TOO_LONG
+--error ER_TOO_LONG_KEY
 create temporary table t (
 	a int not null,
 	b blob not null,
@@ -246,7 +246,7 @@ drop table t;
 SET GLOBAL innodb_large_prefix=default;
 set global innodb_file_per_table = 0;
 #
---error ER_INDEX_COLUMN_TOO_LONG
+--error ER_TOO_LONG_KEY
 create temporary table t (
 	a int not null,
 	b blob not null,
diff --git a/mysql-test/t/alter_table.test b/mysql-test/t/alter_table.test
index 4b7a9aba0741..e5832548829c 100644
--- a/mysql-test/t/alter_table.test
+++ b/mysql-test/t/alter_table.test
@@ -3044,3 +3044,126 @@ ALTER TABLE t1 MODIFY fld0 DATETIME NOT NULL;
 ALTER TABLE t2 MODIFY fld0 POINT NOT NULL;
 
 DROP TABLE t1, t2;
+
+
+--echo #
+--echo # BUG#26848813: INDEXED COLUMN CAN'T BE CHANGED FROM VARCHAR(15)
+--echo #               TO VARCHAR(40) INSTANTANEOUSLY
+
+SET @orig_sql_mode= @@sql_mode;
+SET @orig_innodb_large_prefix= @@global.innodb_large_prefix;
+
+SET GLOBAL innodb_large_prefix= ON;
+
+--echo # Tests where an error is reported under strict mode when the index
+--echo # limit exceeds the maximum supported length by SE.
+
+--error ER_TOO_LONG_KEY
+CREATE TABLE t1 (fld1 VARCHAR(768), KEY(fld1)) CHARSET latin1 ENGINE =InnoDB
+ROW_FORMAT= COMPACT;
+
+--error ER_TOO_LONG_KEY
+CREATE TABLE t2 (fld1 VARCHAR(3073), KEY(fld1)) CHARSET latin1 ENGINE= InnoDB;
+
+--echo # Test with innodb prefix indexes where the index limit is 767 bytes
+CREATE TABLE t1 (fld1 VARCHAR(767), KEY(fld1)) CHARSET latin1 ENGINE=INNODB
+ROW_FORMAT=COMPACT;
+
+--error ER_TOO_LONG_KEY
+ALTER TABLE t1 MODIFY fld1 VARCHAR(768), ALGORITHM= INPLACE;
+
+--error ER_TOO_LONG_KEY
+ALTER TABLE t1 MODIFY fld1 VARCHAR(768), ALGORITHM= COPY;
+
+--echo # Test with innodb prefix indexes where the index limit is 3072 bytes
+CREATE TABLE t2 (fld1 VARCHAR(3072), KEY(fld1)) CHARSET latin1 ENGINE=INNODB
+ROW_FORMAT=DYNAMIC;
+
+--error ER_TOO_LONG_KEY
+ALTER TABLE t2 MODIFY fld1 VARCHAR(3073), ALGORITHM= INPLACE;
+
+--error ER_TOO_LONG_KEY
+ALTER TABLE t2 MODIFY fld1 VARCHAR(3073), ALGORITHM= COPY;
+
+--echo # Tests with innodb_large_prefix disabled and strict mode.
+SET GLOBAL innodb_large_prefix= OFF;
+--error ER_TOO_LONG_KEY
+CREATE TABLE t3 (fld1 VARCHAR(3072), KEY(fld1)) CHARSET latin1 ENGINE= InnoDB;
+
+DROP TABLE t1, t2;
+
+SET sql_mode= '';
+SET GLOBAL innodb_large_prefix= ON;
+
+--enable_warnings
+
+--echo # Test where the indexes are truncated to fit the index limit and
+--echo # a warning is reported under non-strict mode when the index exceeds
+--echo # the SE limit.
+CREATE TABLE t1 (fld1 VARCHAR(768), KEY(fld1)) ENGINE= InnoDB
+ROW_FORMAT=COMPACT;
+CREATE TABLE t2 (fld1 VARCHAR(3073), KEY(fld1)) ENGINE= InnoDB;
+
+--echo # Test with innodb prefix indexes where the index limit is 767 bytes.
+CREATE TABLE t3 (fld1 VARCHAR(767), KEY(fld1))ENGINE=INNODB ROW_FORMAT=COMPACT;
+
+ALTER TABLE t3 MODIFY fld1 VARCHAR(768), ALGORITHM= INPLACE;
+
+ALTER TABLE t3 MODIFY fld1 VARCHAR(800), ALGORITHM= COPY;
+
+--echo # Test with innodb prefix indexes where the index limit is 3072 bytes.
+CREATE TABLE t4 (fld1 VARCHAR(3072), KEY(fld1))ENGINE=INNODB
+ROW_FORMAT=DYNAMIC;
+
+ALTER TABLE t4 MODIFY fld1 VARCHAR(3073), ALGORITHM= INPLACE;
+
+ALTER TABLE t4 MODIFY fld1 VARCHAR(3074), ALGORITHM= COPY;
+
+--echo # For unique and primary keys, an error is reported even in non-strict
+--echo # mode.
+
+--error ER_TOO_LONG_KEY
+CREATE TABLE t5(fld1 VARCHAR(768) PRIMARY KEY) ENGINE= InnoDB
+ROW_FORMAT=COMPACT;
+
+--error ER_TOO_LONG_KEY
+CREATE TABLE t5(fld1 VARCHAR(3073), UNIQUE KEY(fld1)) ENGINE= InnoDB;
+
+--echo # Tests with innodb_large_prefix disabled and strict mode.
+SET GLOBAL innodb_large_prefix= OFF;
+CREATE TABLE t5 (fld1 VARCHAR(3072), KEY(fld1)) CHARSET latin1 ENGINE= InnoDB;
+
+--disable_warnings
+DROP TABLE t1, t2, t3, t4, t5;
+
+SET sql_mode= @orig_sql_mode;
+SET GLOBAL innodb_large_prefix= ON;
+
+--echo # Tests added for coverage.
+CREATE TABLE t1(fld1 VARCHAR(3), KEY(fld1)) ENGINE=MYISAM;
+
+--echo # Conversion of unpacked keys to packed keys reports
+--echo # error for INPLACE Alter.
+--error ER_ALTER_OPERATION_NOT_SUPPORTED
+ALTER TABLE t1 MODIFY fld1 VARCHAR(10), ALGORITHM=INPLACE;
+
+--echo # Succeeds with index rebuild.
+ALTER TABLE t1 MODIFY fld1 VARCHAR(10), ALGORITHM=COPY;
+
+--echo # Succeeds since the row format is dynamic.
+CREATE TABLE t2(fld1 VARCHAR(768), KEY(fld1)) ENGINE= InnoDB ROW_FORMAT= DYNAMIC;
+
+--echo # An error is reported when the index exceeds the column size
+--echo # in both strict and non-strict mode.
+--error ER_WRONG_SUB_KEY
+ALTER TABLE t2 ADD INDEX idx1(fld1(769));
+
+SET sql_mode= '';
+
+--error ER_WRONG_SUB_KEY
+ALTER TABLE t2 ADD INDEX idx1(fld1(769));
+
+--echo # Cleanup.
+DROP TABLE t1, t2;
+SET sql_mode= @orig_sql_mode;
+SET GLOBAL innodb_large_prefix= @orig_innodb_large_prefix;
diff --git a/mysql-test/t/innodb_mysql_sync.test b/mysql-test/t/innodb_mysql_sync.test
index 364e1ab926be..166122697cdf 100644
--- a/mysql-test/t/innodb_mysql_sync.test
+++ b/mysql-test/t/innodb_mysql_sync.test
@@ -1098,6 +1098,34 @@ DROP TABLE t1;
 SET debug="-d,innodb_index_drop_count_zero";
 
 
+--echo #
+--echo # BUG#26848813: INDEXED COLUMN CAN'T BE CHANGED FROM VARCHAR(15)
+--echo #               TO VARCHAR(40) INSTANTANEOUSLY
+
+CREATE TABLE t1(fld1 VARCHAR(5), KEY(fld1)) ENGINE= InnoDB;
+SET DEBUG="+d,innodb_index_drop_count_zero";
+
+--echo # Without patch, an error is reported.
+ALTER TABLE t1 MODIFY fld1 VARCHAR(7), ALGORITHM= INPLACE;
+
+--echo # Scenario where non-packed keys is converted to packed keys
+--echo # before the patch, an error is reported.
+ALTER TABLE t1 MODIFY fld1 VARCHAR(9), ALGORITHM= INPLACE;
+
+SET DEBUG="-d,innodb_index_drop_count_zero";
+
+--echo # Tests added for covering cases where rebuild is required.
+
+--echo # Reducing the size of the field.
+--error ER_ALTER_OPERATION_NOT_SUPPORTED_REASON
+ALTER TABLE t1 MODIFY fld1 VARCHAR(3), ALGORITHM= INPLACE;
+
+--echo # Increasing the size of the field to boundary condition.
+--error ER_ALTER_OPERATION_NOT_SUPPORTED_REASON
+ALTER TABLE t1 MODIFY fld1 VARCHAR(256), ALGORITHM= INPLACE;
+
+DROP TABLE t1;
+
 # Check that all connections opened by test cases in this file are really
 # gone so execution of other tests won't be affected by their presence.
 --source include/wait_until_count_sessions.inc
diff --git a/sql/ha_ndbcluster.cc b/sql/ha_ndbcluster.cc
index 61c345f5e75b..a438a7f340a0 100644
--- a/sql/ha_ndbcluster.cc
+++ b/sql/ha_ndbcluster.cc
@@ -1,4 +1,4 @@
-/* Copyright (c) 2004, 2017, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2004, 2018, Oracle and/or its affiliates. All rights reserved.
 
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -13768,7 +13768,8 @@ uint ha_ndbcluster::max_supported_key_length() const
 {
   return NDB_MAX_KEY_SIZE;
 }
-uint ha_ndbcluster::max_supported_key_part_length() const
+uint ha_ndbcluster::max_supported_key_part_length(HA_CREATE_INFO
+                                 *create_info MY_ATTRIBUTE((unused))) const
 {
   return NDB_MAX_KEY_SIZE;
 }
diff --git a/sql/ha_ndbcluster.h b/sql/ha_ndbcluster.h
index 9d1c75575a1d..3f4cba5524a0 100644
--- a/sql/ha_ndbcluster.h
+++ b/sql/ha_ndbcluster.h
@@ -1,5 +1,5 @@
 /*
-   Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.
+   Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -238,7 +238,7 @@ class ha_ndbcluster: public handler, public Partition_handler
   uint max_supported_keys() const;
   uint max_supported_key_parts() const;
   uint max_supported_key_length() const;
-  uint max_supported_key_part_length() const;
+  uint max_supported_key_part_length(HA_CREATE_INFO *create_info) const;
 
   virtual bool is_fk_defined_on_table_or_index(uint index);
   int get_child_or_parent_fk_list(THD *thd,
diff --git a/sql/handler.cc b/sql/handler.cc
index 78faf46c8ce4..99818b510fb9 100644
--- a/sql/handler.cc
+++ b/sql/handler.cc
@@ -4845,7 +4845,8 @@ handler::check_if_supported_inplace_alter(TABLE *altered_table,
     Alter_inplace_info::CHANGE_CREATE_OPTION |
     Alter_inplace_info::ALTER_RENAME |
     Alter_inplace_info::RENAME_INDEX |
-    Alter_inplace_info::ALTER_INDEX_COMMENT;
+    Alter_inplace_info::ALTER_INDEX_COMMENT |
+    Alter_inplace_info::ALTER_COLUMN_INDEX_LENGTH;
 
   /* Is there at least one operation that requires copy algorithm? */
   if (ha_alter_info->handler_flags & ~inplace_offline_operations)
diff --git a/sql/handler.h b/sql/handler.h
index 3cb113474d66..ca1ca5c3bc3d 100644
--- a/sql/handler.h
+++ b/sql/handler.h
@@ -1030,6 +1030,9 @@ struct handlerton
 
 #define HTON_SUPPORTS_FOREIGN_KEYS   (1 << 11)
 
+// Engine supports packed keys.
+#define HTON_SUPPORTS_PACKED_KEYS    (1 << 12)
+
 enum enum_tx_isolation { ISO_READ_UNCOMMITTED, ISO_READ_COMMITTED,
 			 ISO_REPEATABLE_READ, ISO_SERIALIZABLE};
 
@@ -1325,6 +1328,14 @@ class Alter_inplace_info
   // New/changed virtual generated column require validation
   static const HA_ALTER_FLAGS VALIDATE_VIRTUAL_COLUMN    = 1ULL << 41;
 
+  /**
+    Change in index length such that it does not require index rebuild.
+    For example, change in index length due to column expansion like
+    varchar(X) changed to varchar(X + N).
+  */
+  static const HA_ALTER_FLAGS ALTER_COLUMN_INDEX_LENGTH = 1ULL << 42;
+
+
   /**
     Create options (like MAX_ROWS) for the new version of table.
 
@@ -3074,16 +3085,18 @@ class handler :public Sql_alloc
   {
     return std::min(MAX_KEY_LENGTH, max_supported_key_length());
   }
-  uint max_key_part_length() const
+  uint max_key_part_length(HA_CREATE_INFO *create_info) const
   {
-    return std::min(MAX_KEY_LENGTH, max_supported_key_part_length());
+    return std::min(MAX_KEY_LENGTH, max_supported_key_part_length(create_info));
   }
 
   virtual uint max_supported_record_length() const { return HA_MAX_REC_LENGTH; }
   virtual uint max_supported_keys() const { return 0; }
   virtual uint max_supported_key_parts() const { return MAX_REF_PARTS; }
   virtual uint max_supported_key_length() const { return MAX_KEY_LENGTH; }
-  virtual uint max_supported_key_part_length() const { return 255; }
+  virtual uint max_supported_key_part_length(HA_CREATE_INFO
+                            *create_info MY_ATTRIBUTE((unused))) const
+  { return 255; }
   virtual uint min_record_length(uint options) const { return 1; }
 
   virtual bool low_byte_first() const { return 1; }
diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index ec92483741b9..45f27278a0dc 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -4331,10 +4331,11 @@ mysql_prepare_create_table(THD *thd, const char *error_schema_name,
           size_t max_field_size= blob_length_by_type(sql_field->sql_type);
 	  if (key_part_length > max_field_size ||
               key_part_length > max_key_length ||
-	      key_part_length > file->max_key_part_length())
+	      key_part_length > file->max_key_part_length(create_info))
 	  {
             // Given prefix length is too large, adjust it.
-	    key_part_length= min(max_key_length, file->max_key_part_length());
+	    key_part_length= min(max_key_length,
+                                 file->max_key_part_length(create_info));
 	    if (max_field_size)
               key_part_length= min(key_part_length, max_field_size);
 	    if (key->type == KEYTYPE_MULTIPLE)
@@ -4385,10 +4386,10 @@ mysql_prepare_create_table(THD *thd, const char *error_schema_name,
 	my_error(ER_WRONG_KEY_COLUMN, MYF(0), column->field_name.str);
 	  DBUG_RETURN(TRUE);
       }
-      if (key_part_length > file->max_key_part_length() &&
+      if (key_part_length > file->max_key_part_length(create_info) &&
           key->type != KEYTYPE_FULLTEXT)
       {
-        key_part_length= file->max_key_part_length();
+        key_part_length= file->max_key_part_length(create_info);
 	if (key->type == KEYTYPE_MULTIPLE)
 	{
 	  /* not a critical problem */
@@ -4412,7 +4413,8 @@ mysql_prepare_create_table(THD *thd, const char *error_schema_name,
       }
       key_part_info->length= (uint16) key_part_length;
       /* Use packed keys for long strings on the first column */
-      if (!((*db_options) & HA_OPTION_NO_PACK_KEYS) &&
+      if ((create_info->db_type->flags & HTON_SUPPORTS_PACKED_KEYS) &&
+          !((*db_options) & HA_OPTION_NO_PACK_KEYS) &&
           !((create_info->table_options & HA_OPTION_NO_PACK_KEYS)) &&
 	  (key_part_length >= KEY_DEFAULT_PACK_LENGTH &&
 	   (sql_field->sql_type == MYSQL_TYPE_STRING ||
@@ -6297,18 +6299,30 @@ static bool has_index_def_changed(Alter_inplace_info *ha_alter_info,
        key_part < end;
        key_part++, new_part++)
   {
+
+    new_field= get_field_by_index(alter_info, new_part->fieldnr);
+
     /*
-      Key definition has changed if we are using a different field or
-      if the used key part length is different. It makes sense to
-      check lengths first as in case when fields differ it is likely
-      that lengths differ too and checking fields is more expensive
-      in general case.
+      If there is a change in index length due to column expansion
+      like varchar(X) changed to varchar(X + N) and has a compatible
+      packed data representation, we mark it for fast/INPLACE change
+      in index definition. Some engines like InnoDB supports INPLACE
+      alter for such cases.
+
+      In other cases, key definition has changed if we are using a
+      different field or if the used key part length is different, or
+      key part direction has changed.
     */
-    if (key_part->length != new_part->length)
+    if (key_part->length != new_part->length &&
+        ha_alter_info->alter_info->flags == Alter_info::ALTER_CHANGE_COLUMN &&
+        (key_part->field->is_equal((Create_field *)new_field) == IS_EQUAL_PACK_LENGTH))
+    {
+      ha_alter_info->handler_flags|=
+          Alter_inplace_info::ALTER_COLUMN_INDEX_LENGTH;
+    }
+    else if (key_part->length != new_part->length)
       return true;
 
-    new_field= get_field_by_index(alter_info, new_part->fieldnr);
-
     /*
       For prefix keys KEY_PART_INFO::field points to cloned Field
       object with adjusted length. So below we have to check field
diff --git a/sql/sql_tmp_table.cc b/sql/sql_tmp_table.cc
index 8f5153cc8c78..39d24e852fa6 100644
--- a/sql/sql_tmp_table.cc
+++ b/sql/sql_tmp_table.cc
@@ -462,7 +462,7 @@ void Cache_temp_engine_properties::init(THD *thd)
   db_plugin= ha_lock_engine(0, heap_hton);
   handler= get_new_handler((TABLE_SHARE *)0, thd->mem_root, heap_hton);
   HEAP_MAX_KEY_LENGTH= handler->max_key_length();
-  HEAP_MAX_KEY_PART_LENGTH= handler->max_key_part_length();
+  HEAP_MAX_KEY_PART_LENGTH= handler->max_key_part_length(0);
   HEAP_MAX_KEY_PARTS= handler->max_key_parts();
   delete handler;
   plugin_unlock(0, db_plugin);
@@ -470,7 +470,7 @@ void Cache_temp_engine_properties::init(THD *thd)
   db_plugin= ha_lock_engine(0, myisam_hton);
   handler= get_new_handler((TABLE_SHARE *)0, thd->mem_root, myisam_hton);
   MYISAM_MAX_KEY_LENGTH= handler->max_key_length();
-  MYISAM_MAX_KEY_PART_LENGTH= handler->max_key_part_length();
+  MYISAM_MAX_KEY_PART_LENGTH= handler->max_key_part_length(0);
   MYISAM_MAX_KEY_PARTS= handler->max_key_parts();
   delete handler;
   plugin_unlock(0, db_plugin);
diff --git a/storage/archive/ha_archive.h b/storage/archive/ha_archive.h
index e3b508906425..670254c58869 100644
--- a/storage/archive/ha_archive.h
+++ b/storage/archive/ha_archive.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2003, 2014, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
 
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -118,7 +118,9 @@ class ha_archive: public handler
                                   ulonglong *nb_reserved_values);
   uint max_supported_keys()          const { return 1; }
   uint max_supported_key_length()    const { return sizeof(ulonglong); }
-  uint max_supported_key_part_length() const { return sizeof(ulonglong); }
+  uint max_supported_key_part_length(HA_CREATE_INFO
+                    *create_info MY_ATTRIBUTE((unused))) const
+  { return sizeof(ulonglong); }
   virtual int records(ha_rows *num_rows)
   {
     *num_rows= share->rows_recorded;
diff --git a/storage/blackhole/ha_blackhole.h b/storage/blackhole/ha_blackhole.h
index cb8e25569478..f7a20e4ce3ed 100644
--- a/storage/blackhole/ha_blackhole.h
+++ b/storage/blackhole/ha_blackhole.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.
 
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -69,7 +69,9 @@ class ha_blackhole: public handler
 #define BLACKHOLE_MAX_KEY_LENGTH 1000
   uint max_supported_keys()          const { return BLACKHOLE_MAX_KEY; }
   uint max_supported_key_length()    const { return BLACKHOLE_MAX_KEY_LENGTH; }
-  uint max_supported_key_part_length() const { return BLACKHOLE_MAX_KEY_LENGTH; }
+  uint max_supported_key_part_length(HA_CREATE_INFO
+                        *create_info MY_ATTRIBUTE((unused))) const
+  { return BLACKHOLE_MAX_KEY_LENGTH; }
   int open(const char *name, int mode, uint test_if_locked);
   int close(void);
   int truncate();
diff --git a/storage/federated/ha_federated.h b/storage/federated/ha_federated.h
index f60aa79967ca..650a19df2d3a 100644
--- a/storage/federated/ha_federated.h
+++ b/storage/federated/ha_federated.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2004, 2014, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2004, 2018, Oracle and/or its affiliates. All rights reserved.
 
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -168,7 +168,9 @@ class ha_federated: public handler
   uint max_supported_keys()          const { return MAX_KEY; }
   uint max_supported_key_parts()     const { return MAX_REF_PARTS; }
   uint max_supported_key_length()    const { return FEDERATED_MAX_KEY_LENGTH; }
-  uint max_supported_key_part_length() const { return FEDERATED_MAX_KEY_LENGTH; }
+  uint max_supported_key_part_length(HA_CREATE_INFO
+                    *create_info MY_ATTRIBUTE((unused))) const
+  { return FEDERATED_MAX_KEY_LENGTH; }
   /*
     Called in test_quick_select to determine if indexes should be used.
     Normally, we need to know number of blocks . For federated we need to
diff --git a/storage/heap/ha_heap.h b/storage/heap/ha_heap.h
index cb25623b58fc..9e37047c1ae4 100644
--- a/storage/heap/ha_heap.h
+++ b/storage/heap/ha_heap.h
@@ -1,5 +1,5 @@
 /*
-   Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
+   Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -61,7 +61,9 @@ class ha_heap: public handler
   }
   const key_map *keys_to_use_for_scanning() { return &btree_keys; }
   uint max_supported_keys()          const { return MAX_KEY; }
-  uint max_supported_key_part_length() const { return MAX_KEY_LENGTH; }
+  uint max_supported_key_part_length(HA_CREATE_INFO
+                    *create_info MY_ATTRIBUTE((unused))) const
+  { return MAX_KEY_LENGTH; }
   double scan_time()
   { return (double) (stats.records+stats.deleted) / 20.0+10; }
   double read_time(uint index, uint ranges, ha_rows rows)
diff --git a/storage/innobase/handler/ha_innodb.cc b/storage/innobase/handler/ha_innodb.cc
index 8ce8c184ef31..f1cba471384b 100644
--- a/storage/innobase/handler/ha_innodb.cc
+++ b/storage/innobase/handler/ha_innodb.cc
@@ -6345,14 +6345,23 @@ ha_innobase::clone(
 
 
 uint
-ha_innobase::max_supported_key_part_length() const
+ha_innobase::max_supported_key_part_length(HA_CREATE_INFO *create_info) const
 /*==============================================*/
 {
 	/* A table format specific index column length check will be performed
 	at ha_innobase::add_index() and row_create_index_for_mysql() */
-	return(innobase_large_prefix
-		? REC_VERSION_56_MAX_INDEX_COL_LEN
-		: REC_ANTELOPE_MAX_INDEX_COL_LEN - 1);
+	switch (create_info->row_type) {
+	case ROW_TYPE_REDUNDANT:
+	case ROW_TYPE_COMPACT:
+		return (REC_ANTELOPE_MAX_INDEX_COL_LEN - 1);
+		break;
+	default:
+		if (innobase_large_prefix)
+			return (REC_VERSION_56_MAX_INDEX_COL_LEN);
+		else
+			return (REC_ANTELOPE_MAX_INDEX_COL_LEN - 1);
+	}
+
 }
 
 /******************************************************************//**
diff --git a/storage/innobase/handler/ha_innodb.h b/storage/innobase/handler/ha_innodb.h
index b83b70cb4463..9d7150a2679c 100644
--- a/storage/innobase/handler/ha_innodb.h
+++ b/storage/innobase/handler/ha_innodb.h
@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-Copyright (c) 2000, 2017, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2000, 2018, Oracle and/or its affiliates. All Rights Reserved.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -91,7 +91,7 @@ class ha_innobase: public handler
 
 	uint max_supported_key_length() const;
 
-	uint max_supported_key_part_length() const;
+	uint max_supported_key_part_length(HA_CREATE_INFO *create_info) const;
 
 	const key_map* keys_to_use_for_scanning();
 
diff --git a/storage/innobase/handler/handler0alter.cc b/storage/innobase/handler/handler0alter.cc
index 8d28fa567244..4683084e3047 100644
--- a/storage/innobase/handler/handler0alter.cc
+++ b/storage/innobase/handler/handler0alter.cc
@@ -110,7 +110,8 @@ static const Alter_inplace_info::HA_ALTER_FLAGS INNOBASE_ALTER_NOREBUILD
 	| Alter_inplace_info::ALTER_INDEX_COMMENT
 	| Alter_inplace_info::ADD_VIRTUAL_COLUMN
 	| Alter_inplace_info::DROP_VIRTUAL_COLUMN
-	| Alter_inplace_info::ALTER_VIRTUAL_COLUMN_ORDER;
+	| Alter_inplace_info::ALTER_VIRTUAL_COLUMN_ORDER
+        | Alter_inplace_info::ALTER_COLUMN_INDEX_LENGTH;
 	/* | Alter_inplace_info::ALTER_VIRTUAL_COLUMN_TYPE; */
 
 struct ha_innobase_inplace_ctx : public inplace_alter_handler_ctx
diff --git a/storage/myisam/ha_myisam.cc b/storage/myisam/ha_myisam.cc
index e934a59ffec8..5f30a0c0f852 100644
--- a/storage/myisam/ha_myisam.cc
+++ b/storage/myisam/ha_myisam.cc
@@ -2299,7 +2299,8 @@ static int myisam_init(void *p)
   myisam_hton->create= myisam_create_handler;
   myisam_hton->panic= myisam_panic;
   myisam_hton->close_connection= myisam_close_connection;
-  myisam_hton->flags= HTON_CAN_RECREATE | HTON_SUPPORT_LOG_TABLES;
+  myisam_hton->flags= HTON_CAN_RECREATE | HTON_SUPPORT_LOG_TABLES |
+                      HTON_SUPPORTS_PACKED_KEYS;
   myisam_hton->is_supported_system_table= myisam_is_supported_system_table;
 
   main_thread_keycache_var= st_keycache_thread_var();
diff --git a/storage/myisam/ha_myisam.h b/storage/myisam/ha_myisam.h
index f7794b7c85fc..11890c26032b 100644
--- a/storage/myisam/ha_myisam.h
+++ b/storage/myisam/ha_myisam.h
@@ -1,5 +1,5 @@
 /*
-   Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.
+   Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -83,7 +83,9 @@ class ha_myisam: public handler
   }
   uint max_supported_keys()          const { return MI_MAX_KEY; }
   uint max_supported_key_length()    const { return MI_MAX_KEY_LENGTH; }
-  uint max_supported_key_part_length() const { return MI_MAX_KEY_LENGTH; }
+  uint max_supported_key_part_length(HA_CREATE_INFO
+                    *create_info MY_ATTRIBUTE((unused))) const
+  { return MI_MAX_KEY_LENGTH; }
   uint checksum() const;
 
   int open(const char *name, int mode, uint test_if_locked);
diff --git a/storage/myisammrg/ha_myisammrg.h b/storage/myisammrg/ha_myisammrg.h
index 2f91986d1f47..9d201ddc769c 100644
--- a/storage/myisammrg/ha_myisammrg.h
+++ b/storage/myisammrg/ha_myisammrg.h
@@ -1,5 +1,5 @@
 /*
-   Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved.
+   Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -99,7 +99,9 @@ class ha_myisammrg: public handler
   }
   uint max_supported_keys()          const { return MI_MAX_KEY; }
   uint max_supported_key_length()    const { return MI_MAX_KEY_LENGTH; }
-  uint max_supported_key_part_length() const { return MI_MAX_KEY_LENGTH; }
+  uint max_supported_key_part_length(HA_CREATE_INFO
+                    *create_info MY_ATTRIBUTE((unused))) const
+  { return MI_MAX_KEY_LENGTH; }
   double scan_time()
   { return ulonglong2double(stats.data_file_length) / IO_SIZE + file->tables; }
 
diff --git a/storage/partition/ha_partition.cc b/storage/partition/ha_partition.cc
index de8348ff988d..f3258dc375d0 100644
--- a/storage/partition/ha_partition.cc
+++ b/storage/partition/ha_partition.cc
@@ -5551,6 +5551,21 @@ uint ha_partition::min_of_the_max_uint(
 }
 
 
+uint ha_partition::min_of_the_max_uint(HA_CREATE_INFO *create_info,
+                       uint (handler::*operator_func)(HA_CREATE_INFO *) const) const
+{
+  handler **file;
+  uint min_of_the_max= ((*m_file)->*operator_func)(create_info);
+
+  for (file= m_file+1; *file; file++)
+  {
+    uint tmp= ((*file)->*operator_func)(create_info);
+    set_if_smaller(min_of_the_max, tmp);
+  }
+  return min_of_the_max;
+}
+
+
 uint ha_partition::max_supported_key_parts() const
 {
   return min_of_the_max_uint(&handler::max_supported_key_parts);
@@ -5563,9 +5578,11 @@ uint ha_partition::max_supported_key_length() const
 }
 
 
-uint ha_partition::max_supported_key_part_length() const
+uint ha_partition::max_supported_key_part_length(HA_CREATE_INFO
+                                                 *create_info) const
 {
-  return min_of_the_max_uint(&handler::max_supported_key_part_length);
+  return
+  min_of_the_max_uint(create_info, &handler::max_supported_key_part_length);
 }
 
 
diff --git a/storage/partition/ha_partition.h b/storage/partition/ha_partition.h
index 2f7311e10c6e..f5be20d95004 100644
--- a/storage/partition/ha_partition.h
+++ b/storage/partition/ha_partition.h
@@ -2,7 +2,7 @@
 #define HA_PARTITION_INCLUDED
 
 /*
-   Copyright (c) 2005, 2017, Oracle and/or its affiliates. All rights reserved.
+   Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -902,11 +902,13 @@ class ha_partition :
     The maximum supported values is the minimum of all handlers in the table
   */
   uint min_of_the_max_uint(uint (handler::*operator_func)(void) const) const;
+  uint min_of_the_max_uint(HA_CREATE_INFO *create_info,
+                           uint (handler::*operator_func)(HA_CREATE_INFO *) const) const;
   virtual uint max_supported_record_length() const;
   virtual uint max_supported_keys() const;
   virtual uint max_supported_key_parts() const;
   virtual uint max_supported_key_length() const;
-  virtual uint max_supported_key_part_length() const;
+  virtual uint max_supported_key_part_length(HA_CREATE_INFO *create_info) const;
 
   /*
     All handlers in a partitioned table must have the same low_byte_first