diff --git a/include/query_processor.h b/include/query_processor.h index 9d6233029..fd93abb71 100644 --- a/include/query_processor.h +++ b/include/query_processor.h @@ -164,7 +164,7 @@ class Query_Processor_Output { mirror_flagOUT=-1; next_query_flagIN=-1; cache_ttl=-1; - cache_empty_result=1; + cache_empty_result=-1; cache_timeout=-1; reconnect=-1; timeout=-1; diff --git a/test/tap/tests/mysql-reg_test_4723_query_cache_stores_empty_result-t.cpp b/test/tap/tests/mysql-reg_test_4723_query_cache_stores_empty_result-t.cpp new file mode 100644 index 000000000..d36c5d53b --- /dev/null +++ b/test/tap/tests/mysql-reg_test_4723_query_cache_stores_empty_result-t.cpp @@ -0,0 +1,168 @@ +/** + * @file mysql-reg_test_4723_query_cache_stores_empty_result-t.cpp + * @brief This test verfies that 'mysql-query_cache_stores_empty_result' variable works as expected. + * Specifically, it ensures that when this variable is set to `0`, empty results (zero rows) + * are not cached, and when set to `1`, they are cached. + * The test verifies this behavior by comparing the metrics before and after query execution. + */ + +#include +#include + +#include "mysql.h" +#include "command_line.h" +#include "tap.h" +#include "utils.h" + +CommandLine cl; + +std::map getQueryCacheMetrics(MYSQL* proxy_admin) { + const char* query = "SELECT Variable_Name, Variable_Value FROM stats_mysql_global WHERE Variable_Name LIKE 'Query_Cache%';"; + diag("Running: %s", query); + + int query_res = mysql_query(proxy_admin, query); + if (query_res) { + BAIL_OUT("Query failed with error: %s", mysql_error(proxy_admin)); + return {}; + } + + std::map metrics{}; + MYSQL_RES* res = mysql_store_result(proxy_admin); + if (!res) { + BAIL_OUT("Failed to store result: %s", mysql_error(proxy_admin)); + return {}; + } + + MYSQL_ROW row; + while ((row = mysql_fetch_row(res))) { + metrics[row[0]] = atoi(row[1]); + } + + mysql_free_result(res); + return metrics; +} + +class TestMetrics { +public: + std::map before; + std::map after; + + void swap() { + before.swap(after); + } + + template + bool checkMetricDelta(const std::string& metric_name, int expected, BinaryOp op) { + if (before.find(metric_name) == before.end() || after.find(metric_name) == after.end()) { + diag("Metric '%s' not found in either before or after map.", metric_name.c_str()); + return false; + } + + int delta = after[metric_name] - before[metric_name]; + bool result = op(std::max(0, delta), expected); + + diag("Checking metric '%s': Expected delta %d, Actual delta %d", metric_name.c_str(), expected, delta); + ok(result, "Metric `%s` delta is correct. Expected '%d', got '%d'", metric_name.c_str(), expected, delta); + return result; + } +}; + +// Helper function for executing MySQL queries with error handling +bool exec_query(MYSQL* conn, const char* query) { + diag("Running query: %s", query); + int query_res = mysql_query(conn, query); + if (query_res) { + diag("Query failed with error: %s", mysql_error(conn)); + return false; + } + return true; +} + +int main(int argc, char** argv) { + plan(10); // Total number of tests planned + + if (cl.getEnv()) + return exit_status(); + + // Initialize and connect to ProxySQL Admin + MYSQL* proxysql_admin = mysql_init(nullptr); + if (!proxysql_admin) { + BAIL_OUT("MySQL admin init failed."); + } + + if (!mysql_real_connect(proxysql_admin, cl.admin_host, cl.admin_username, cl.admin_password, nullptr, cl.admin_port, nullptr, 0)) { + BAIL_OUT("Failed to connect to ProxySQL Admin: %s", mysql_error(proxysql_admin)); + } + + // Initialize and connect to ProxySQL Backend + MYSQL* proxysql_backend = mysql_init(nullptr); + if (!proxysql_backend) { + BAIL_OUT("MySQL backend init failed."); + } + + if (!mysql_real_connect(proxysql_backend, cl.host, cl.username, cl.password, nullptr, cl.port, nullptr, 0)) { + BAIL_OUT("Failed to connect to ProxySQL Backend: %s", mysql_error(proxysql_backend)); + } + + // Setting up test environment + MYSQL_QUERY(proxysql_admin, "DELETE FROM mysql_query_rules"); + MYSQL_QUERY(proxysql_admin, "INSERT INTO mysql_query_rules (rule_id,active,match_digest,cache_ttl) VALUES (2,1,'^SELECT',4000)"); + MYSQL_QUERY(proxysql_admin, "LOAD MYSQL QUERY RULES TO RUNTIME"); + + // Disable query cache storing empty result + MYSQL_QUERY(proxysql_admin, "UPDATE global_variables SET variable_value=0 WHERE variable_name='mysql-query_cache_stores_empty_result'"); + MYSQL_QUERY(proxysql_admin, "LOAD MYSQL VARIABLES TO RUNTIME"); + + TestMetrics metrics; + + metrics.before = getQueryCacheMetrics(proxysql_admin); + + // Execute the test query and check the result + if (exec_query(proxysql_backend, "SELECT 1 FROM DUAL WHERE 1!=1")) { + MYSQL_RES* res = mysql_store_result(proxysql_backend); + ok(res != nullptr, "Query executed successfully."); + mysql_free_result(res); + } + else { + ok(false, "Error executing query."); + } + + // Fetch metrics after query execution + metrics.after = getQueryCacheMetrics(proxysql_admin); + + metrics.checkMetricDelta("Query_Cache_Memory_bytes", 0, std::equal_to()); + metrics.checkMetricDelta("Query_Cache_count_SET", 0, std::equal_to()); + metrics.checkMetricDelta("Query_Cache_bytes_IN", 0, std::equal_to()); + metrics.checkMetricDelta("Query_Cache_Entries", 0, std::equal_to()); + + // Swap the before and after metrics for the next phase + metrics.swap(); + + // Enable query cache storing empty result + MYSQL_QUERY(proxysql_admin, "UPDATE global_variables SET variable_value=1 WHERE variable_name='mysql-query_cache_stores_empty_result'"); + MYSQL_QUERY(proxysql_admin, "LOAD MYSQL VARIABLES TO RUNTIME"); + + // Execute the same query again and check the result + if (exec_query(proxysql_backend, "SELECT 1 FROM DUAL WHERE 1!=1")) { + MYSQL_RES* res = mysql_store_result(proxysql_backend); + ok(res != nullptr, "Query executed successfully."); + mysql_free_result(res); + } + else { + ok(false, "Error executing query."); + } + + // Fetch metrics again and check for expected changes + metrics.after = getQueryCacheMetrics(proxysql_admin); + + metrics.checkMetricDelta("Query_Cache_Memory_bytes", 1, std::greater()); + metrics.checkMetricDelta("Query_Cache_count_SET", 1, std::equal_to()); + metrics.checkMetricDelta("Query_Cache_bytes_IN", 1, std::greater()); + metrics.checkMetricDelta("Query_Cache_Entries", 1, std::equal_to()); + + // Close the connections + mysql_close(proxysql_backend); + mysql_close(proxysql_admin); + + return exit_status(); +}