diff --git a/lib/MySQL_Session.cpp b/lib/MySQL_Session.cpp index e74252b382..966270e3ad 100644 --- a/lib/MySQL_Session.cpp +++ b/lib/MySQL_Session.cpp @@ -2478,8 +2478,24 @@ bool MySQL_Session::handler_again___status_SETTING_GENERIC_VARIABLE(int *_rc, co else { sprintf(query,q,"tx_isolation", var_value); } - } - else { + } else if (strncasecmp("aurora_read_replica_read_committed", var_name, 34) == 0) { + // If aurora_read_replica_read_committed is set, isolation level is + // internally reset so that it will be set again. + // This solves the weird behavior in AWS Aurora related to isolation level + // as described in + // https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraMySQL.Reference.html#AuroraMySQL.Reference.IsolationLevels + // Basically, to change isolation level you must first set + // aurora_read_replica_read_committed , and then isolation level + MySQL_Connection *beconn = mybe->server_myds->myconn; + if (beconn->var_hash[SQL_ISOLATION_LEVEL] != 0) { + beconn->var_hash[SQL_ISOLATION_LEVEL] = 0; + if (beconn->variables[SQL_ISOLATION_LEVEL].value) { + free(beconn->variables[SQL_ISOLATION_LEVEL].value); + beconn->variables[SQL_ISOLATION_LEVEL].value = NULL; + } + } + sprintf(query,q,var_name, var_value); + } else { sprintf(query,q,var_name, var_value); } query_length=strlen(query);