MDEV-7655 SHOW CREATE TABLE returns invalid DDL when using virtual columns along with a table collation

Author: vuvova

mysql-test/suite/vcol/r/vcol_misc.result

@@ -322,3 +322,11 @@ drop table t1;
 create table t1 (a int, b int as (b is null) virtual);
 ERROR HY000: A computed column cannot be based on a computed column
 # end of 5.3 tests
+create table t1 (v1 varchar(255) as (c1) persistent, c1 varchar(50)) collate=latin1_general_ci;
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `v1` varchar(255) AS (c1) PERSISTENT,
+  `c1` varchar(50) COLLATE latin1_general_ci DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_general_ci
+drop table t1;

mysql-test/suite/vcol/t/vcol_misc.test

@@ -283,3 +283,10 @@ drop table t1;
 create table t1 (a int, b int as (b is null) virtual);
 
 --echo # end of 5.3 tests
+
+#
+# MDEV-7655 SHOW CREATE TABLE returns invalid DDL when using virtual columns along with a table collation
+#
+create table t1 (v1 varchar(255) as (c1) persistent, c1 varchar(50)) collate=latin1_general_ci;
+show create table t1;
+drop table t1;

sql/sql_show.cc

@@ -1611,7 +1611,7 @@ int store_create_info(THD *thd, TABLE_LIST *table_list, String *packet,
 	For string types dump collation name only if
 	collation is not primary for the given charset
       */
-      if (!(field->charset()->state & MY_CS_PRIMARY))
+      if (!(field->charset()->state & MY_CS_PRIMARY) && !field->vcol_info)
       {
 	packet->append(STRING_WITH_LEN(" COLLATE "));
 	packet->append(field->charset()->name);