diff --git a/pkg/index/mysql/dbschema.go b/pkg/index/mysql/dbschema.go
index 28cf64464..81bd23ac3 100644
--- a/pkg/index/mysql/dbschema.go
+++ b/pkg/index/mysql/dbschema.go
@@ -16,20 +16,26 @@ limitations under the License.
 
 package mysql
 
-const requiredSchemaVersion = 20
+const requiredSchemaVersion = 21
 
 func SchemaVersion() int {
 	return requiredSchemaVersion
 }
 
+// Note: using character set "binary", as any knowledge
+// of character set encodings is handled by higher layers.
+// At this layer we're just obeying the IndexStorage interface,
+// which is purely about bytes.
 func SQLCreateTables() []string {
 	return []string{
 		`CREATE TABLE rows (
  k VARCHAR(255) NOT NULL PRIMARY KEY,
- v VARCHAR(255))`,
+ v VARCHAR(255))
+ DEFAULT CHARACTER SET binary`,
 
 		`CREATE TABLE meta (
  metakey VARCHAR(255) NOT NULL PRIMARY KEY,
- value VARCHAR(255) NOT NULL)`,
+ value VARCHAR(255) NOT NULL)
+ DEFAULT CHARACTER SET binary`,
 	}
 }
diff --git a/pkg/index/mysql/mysqlindexer.go b/pkg/index/mysql/mysqlindexer.go
index bb921f723..68936a87f 100644
--- a/pkg/index/mysql/mysqlindexer.go
+++ b/pkg/index/mysql/mysqlindexer.go
@@ -42,7 +42,7 @@ var _ index.Storage = (*myIndexStorage)(nil)
 // This exists mostly for testing and does not initialize the schema.
 func NewStorage(host, user, password, dbname string) (index.Storage, error) {
 	// TODO(bradfitz): host is ignored; how to plumb it through with mymysql?
-	dsn := dbname+"/"+user+"/"+password
+	dsn := dbname + "/" + user + "/" + password
 	db, err := sql.Open("mymysql", dsn)
 	if err != nil {
 		return nil, err
@@ -60,6 +60,12 @@ func NewStorage(host, user, password, dbname string) (index.Storage, error) {
 	}, nil
 }
 
+const fixSchema20to21 = `Character set in tables changed to binary, you can fix your tables with:
+ALTER TABLE rows CONVERT TO CHARACTER SET binary;
+ALTER TABLE meta CONVERT TO CHARACTER SET binary;
+UPDATE meta SET value=21 WHERE metakey='version' AND value=20;
+`
+
 func newFromConfig(ld blobserver.Loader, config jsonconfig.Obj) (blobserver.Storage, error) {
 	var (
 		blobPrefix = config.RequiredString("blobSource")
@@ -89,6 +95,9 @@ func newFromConfig(ld blobserver.Loader, config jsonconfig.Obj) (blobserver.Stor
 		return nil, fmt.Errorf("error getting schema version (need to init database?): %v", err)
 	}
 	if version != requiredSchemaVersion {
+		if version == 20 && requiredSchemaVersion == 21 {
+			fmt.Fprintf(os.Stderr, fixSchema20to21)
+		}
 		if os.Getenv("CAMLI_ADVERTISED_PASSWORD") != "" {
 			// Good signal that we're using the dev-server script, so help out
 			// the user with a more useful tip: