Set 'max_replication_lag' and an extra wait for test 'reg_test_1574-s…

…tmt_metadata-t' to avoid replication lag issues in CI

test/tap/tests/reg_test_1574-stmt_metadata-t.cpp

@@ -83,6 +83,11 @@ int main(int argc, char** argv) {
 		return exit_status();
 	}
 
+	// Set a replication lag inferior to default one (60). This is to prevent reads
+	// from a replica in which replication is currently disabled.
+	MYSQL_QUERY(proxysql_admin, "UPDATE mysql_servers SET max_replication_lag=20");
+	MYSQL_QUERY(proxysql_admin, "LOAD MYSQL SERVERS TO RUNTIME");
+
 	MYSQL_QUERY(proxysql_mysql, "CREATE DATABASE IF NOT EXISTS test");
 	MYSQL_QUERY(proxysql_mysql, "DROP TABLE IF EXISTS test.reg_test_1574");
 	MYSQL_QUERY(proxysql_mysql, "CREATE TABLE IF NOT EXISTS test.reg_test_1574 (id INT NOT NULL AUTO_INCREMENT PRIMARY KEY, `c2` varchar(32))");
@@ -111,6 +116,9 @@ int main(int argc, char** argv) {
 	MYSQL_QUERY(proxysql_mysql, "ALTER TABLE test.reg_test_1574 ADD c1 BIGINT AFTER id");
 	MYSQL_QUERY(proxysql_mysql, "INSERT INTO test.reg_test_1574 (c1,c2) VALUES (100, 'abcde')");
 
+	// Wait for ProxySQL to detect replication issues and in case of slow replication itself
+	sleep(10);
+
 	// Check that ProxySQL cached metadata for the query has the old information
 	std::string num_columns_query_t = "SELECT num_columns FROM stats.stats_mysql_prepared_statements_info WHERE query='%s'";
 	std::string num_columns_query (static_cast<std::size_t>(num_columns_query_t.size() + query.size()), '\0');
@@ -183,7 +191,7 @@ int main(int argc, char** argv) {
 
 	ok(
 		data_match_expected,
-		"Prepared statement result matches expected - Exp=(id:1, c1:100, c2:'abcde'), Act=(id:%d, c1:%d, c2:'%s')",
+		"Prepared statement result matches expected - Exp=(id:1, c1:100, c2:'abcde'), Act=(id:%d, c1:%ld, c2:'%s')",
 		data_id,
 		data_c1,
 		data_c2