Merge branch '2.3' into 2.4

system-test/mxs1713_lots_of_databases.cpp

@@ -0,0 +1,67 @@
+/**
+ * MXS-1713: SchemaRouter unable to process SHOW DATABASES for a lot of schemas
+ *
+ * https://jira.mariadb.org/browse/MXS-1713
+ */
+#include <maxtest/testconnections.hh>
+#include <vector>
+#include <set>
+#include <numeric>
+
+int main(int argc, char** argv)
+{
+    TestConnections test(argc, argv);
+    const int n_db = 2000;
+    std::vector<std::string> db_list;
+
+    for (int i = 0; i < n_db; i++)
+    {
+        db_list.push_back("db" + std::to_string(i));
+    }
+
+    test.tprintf("Create %lu databases...", db_list.size());
+    test.repl->connect();
+    for (auto db : db_list)
+    {
+        execute_query(test.repl->nodes[0], "CREATE DATABASE %s", db.c_str());
+    }
+    test.repl->sync_slaves();
+    test.tprintf("Done!");
+
+    test.tprintf("Opening a connection with each database as the default database...", db_list.size());
+    std::set<std::string> errors;
+    int i = 0;
+
+    for (auto db : db_list)
+    {
+        MYSQL* conn = open_conn_db(test.maxscales->port(),
+                                   test.maxscales->ip(),
+                                   db,
+                                   test.maxscales->user_name,
+                                   test.maxscales->password);
+
+        test.expect(execute_query(conn, "SELECT 1") == 0, "Query should work: %s", mysql_error(conn));
+
+        if (i++ % 300 == 0)
+        {
+            test.expect(execute_query(conn, "SHOW DATABASES") == 0, "Query should work: %s", mysql_error(conn));
+        }
+
+        mysql_close(conn);
+
+        if (test.global_result)
+        {
+            break;
+        }
+    }
+    test.tprintf("Done!");
+
+    test.tprintf("Dropping databases...");
+    for (auto db : db_list)
+    {
+        execute_query(test.repl->nodes[0], "DROP DATABASE %s", db.c_str());
+    }
+    test.tprintf("Done!");
+
+    return test.global_result;
+}