Tengo una consulta de cálculo de recuento que estoy ejecutando miles de veces en mi aplicación Rails, una vez por cada cliente en la base de datos.Rails MySQL confusión de tiempo de consulta
Cuando ejecuto la consulta en mi cliente MySQL con el caché de consultas desactivado, la consulta tarda más de 1ms.
Sin embargo, cuando ejecuto mi tarea desde la consola de Rails con salida de consulta habilitada, me he dado cuenta de que después de las primeras consultas que son muy rápidas el tiempo aumenta súbitamente de menos de 1ms a aproximadamente 180ms para el resto del consultas.
He reducido el innodb_buffer_pool_size para ver un cambio en el comportamiento pero no he notado nada.
Aquí está la salida de la consola:
EmailCampaignReport::Open Columns (143.2ms) SHOW FIELDS FROM `email_campaign_report_opens`
SQL (0.3ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332330)
SQL (0.2ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 333333)
SQL (0.2ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332661)
SQL (0.1ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332326)
SQL (0.1ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332665)
SQL (0.2ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 336027)
SQL (0.2ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 333001)
SQL (0.2ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 331983)
SQL (0.1ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332668)
SQL (0.1ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332316)
SQL (0.1ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332325)
SQL (0.1ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 331995)
SQL (0.2ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 334007)
SQL (0.2ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 333326)
SQL (0.1ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332998)
SQL (183.9ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 334673)
SQL (183.7ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 336751)
SQL (183.6ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 333334)
SQL (186.3ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332663)
SQL (183.7ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332328)
SQL (186.3ms) SELECT count(*) AS count_all FROM `email_campaign_report_opens` WHERE (customer_id = 332659)
No es un índice en la columna de la customer_id en esa tabla.
¿Alguien ha recibido alguna sugerencia de por qué esto estaría sucediendo?
Gracias
¿Puedes publicar el esquema de tu tabla para que podamos ver el índice, etc.? – UltimateBrent