made the mysql 5.7 tables with sizes query less fragile

Signed-off-by: Andres Taylor <[email protected]>

go/mysql/flavor_mysql.go

@@ -249,10 +249,19 @@ func (mysqlFlavor) disableBinlogPlaybackCommand() string {
 const TablesWithSize56 = `SELECT table_name, table_type, unix_timestamp(create_time), table_comment, SUM( data_length + index_length), SUM( data_length + index_length) 
 		FROM information_schema.tables WHERE table_schema = database() group by table_name`
 
-// TablesWithSize57 is a query to select table along with size for mysql 5.7
-const TablesWithSize57 = `SELECT t.table_name, t.table_type, unix_timestamp(t.create_time), t.table_comment, i.file_size, i.allocated_size 
-		FROM information_schema.tables t, information_schema.innodb_sys_tablespaces i 
-		WHERE t.table_schema = database() and i.name = concat(t.table_schema,'/',t.table_name)`
+// TablesWithSize57 is a query to select table along with size for mysql 5.7.
+// It's a little weird, because the JOIN predicate only works if the table and databases do not contain weird characters.
+// As a fallback, we use the mysql 5.6 query, which is not always up to date, but works for all table/db names.
+const TablesWithSize57 = `
+	SELECT t.table_name, t.table_type, unix_timestamp(t.create_time), t.table_comment, i.file_size, i.allocated_size 
+	FROM information_schema.tables t, information_schema.innodb_sys_tablespaces i 
+	WHERE t.table_schema = database() and i.name = concat(t.table_schema,'/',t.table_name)
+UNION ALL
+	SELECT table_name, table_type, unix_timestamp(create_time), table_comment, SUM( data_length + index_length), SUM( data_length + index_length)
+	FROM information_schema.tables 
+	WHERE table_schema = database() AND NOT EXISTS(SELECT * FROM information_schema.tables t, information_schema.innodb_sys_tablespaces i WHERE t.table_schema = database() and i.name = concat(t.table_schema,'/',t.table_name)) 
+	group by table_name
+`
 
 // TablesWithSize80 is a query to select table along with size for mysql 8.0
 const TablesWithSize80 = `SELECT t.table_name, t.table_type, unix_timestamp(t.create_time), t.table_comment, i.file_size, i.allocated_size