Author: sachinagarwal1111

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

@@ -198,3 +198,16 @@ ALTER TABLE t1 ADD COLUMN col7a INT GENERATED ALWAYS AS (col1 % col2)
 VIRTUAL, ADD UNIQUE index idx (col1), algorithm=inplace;
 ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: INPLACE ADD or DROP of virtual columns cannot be combined with other ALTER TABLE actions. Try ALGORITHM=COPY.
 DROP TABLE t1;
+#
+# Bug 27122803 - BACKPORT FIX FOR BUG 25899959 TO MYSQL-5.7
+#
+CREATE TABLE t1 (col1 int(10)) DEFAULT CHARSET=utf8mb4;
+ALTER TABLE t1 ADD col2 char(21) AS (col1 * col1), ADD INDEX n (col2);
+SHOW CREATE TABLE t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `col1` int(10) DEFAULT NULL,
+  `col2` char(21) GENERATED ALWAYS AS ((`col1` * `col1`)) VIRTUAL,
+  KEY `n` (`col2`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4
+DROP TABLE t1;

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

@@ -218,3 +218,13 @@ ALTER TABLE t1 ADD COLUMN col7a INT GENERATED ALWAYS AS (col1 % col2)
 VIRTUAL, ADD UNIQUE index idx (col1), algorithm=inplace;
 
 DROP TABLE t1;
+
+--echo #
+--echo # Bug 27122803 - BACKPORT FIX FOR BUG 25899959 TO MYSQL-5.7
+--echo #
+
+CREATE TABLE t1 (col1 int(10)) DEFAULT CHARSET=utf8mb4;
+ALTER TABLE t1 ADD col2 char(21) AS (col1 * col1), ADD INDEX n (col2);
+SHOW CREATE TABLE t1;
+
+DROP TABLE t1;

storage/innobase/handler/handler0alter.cc

@@ -4251,6 +4251,19 @@ prepare_inplace_alter_table_dict(
 		for create index */
 		if (ha_alter_info->handler_flags
 		    & Alter_inplace_info::ADD_INDEX) {
+                        for (ulint i = 0;
+                             i < ctx->num_to_add_vcol;
+                             i++) {
+                                /* Set mbminmax for newly added column */
+                                ulint   i_mbminlen, i_mbmaxlen;
+                                dtype_get_mblen(ctx->add_vcol[i].m_col.mtype,
+                                                ctx->add_vcol[i].m_col.prtype,
+                                                &i_mbminlen, &i_mbmaxlen);
+
+				dtype_set_mbminmaxlen(
+					(dtype_t*) &ctx->add_vcol[i].m_col,
+					i_mbminlen, i_mbmaxlen);
+                        }
 			add_v = static_cast<dict_add_v_col_t*>(
 				mem_heap_alloc(ctx->heap, sizeof *add_v));
 			add_v->n_v_col = ctx->num_to_add_vcol;