schemadiff INSTANT DDL: impossible on tables with FULLTEXT oindex

Signed-off-by: Shlomi Noach <[email protected]>

go/vt/schemadiff/capability.go

@@ -10,6 +10,12 @@ import (
 // alterOptionAvailableViaInstantDDL checks if the specific alter option is eligible to run via ALGORITHM=INSTANT
 // reference: https://dev.mysql.com/doc/refman/8.0/en/innodb-online-ddl-operations.html
 func alterOptionCapableOfInstantDDL(alterOption sqlparser.AlterOption, createTable *sqlparser.CreateTable, capableOf capabilities.CapableOf) (bool, error) {
+	// A table with FULLTEXT index can't have any sort of INSTANT DDL
+	for _, key := range createTable.TableSpec.Indexes {
+		if key.Info.Type == sqlparser.IndexTypeFullText {
+			return false, nil
+		}
+	}
 	findColumn := func(colName string) *sqlparser.ColumnDefinition {
 		if createTable == nil {
 			return nil

go/vt/schemadiff/capability_test.go

@@ -97,6 +97,12 @@ func TestAlterTableCapableOfInstantDDL(t *testing.T) {
 			alter:                     "alter table t drop column i1",
 			expectCapableOfInstantDDL: false,
 		},
+		{
+			name:                      "drop column fail due to fulltext index in table",
+			create:                    "create table t(id int, i1 int not null, name varchar(128), primary key(id), fulltext key (name))",
+			alter:                     "alter table t drop column i1",
+			expectCapableOfInstantDDL: false,
+		},
 		{
 			name:                      "add two columns",
 			create:                    "create table t(id int, i1 int not null, primary key(id))",