Query lenta: join multipli e molti dati

Question

Sono sicuro che esiste un modo migliore per farlo.Ho tre tabelle principali con grandi quantità di dati da esaminare:records_main, vendite e appuntamenti.Ciascuno con quasi 20.000 record.

Devo unire questi tre tavoli e alcuni altri che non siano due grandi.

    $SQL = "SELECT DISTINCT appointments.id AS aid, appointments.date, appointments.estimate_price, appointments.next_action, appointments.next_action_date, appointments.result, appointments.result_type, appointments.notes,
customer.id AS cid, customer.homeowner1_fname, customer.homeowner1_lname, customer.address, customer.city, customer.state, customer.zipcode, customer.phone1, customer.phone1_type, customer.phone2, customer.phone2_type, customer.phone3, customer.phone3_type, customer.phone4, customer.phone4_type, customer.phone5, customer.phone5_type, customer.lead_source, customer.lead_category, customer.primary_interest, customer.secondary_interest, customer.additional_interest1, customer.additional_interest2,
originator.employee_id AS originator_employee_id,originator.fname AS originator_fname,originator.lname AS originator_lname,
setter.employee_id AS setter_employee_id,setter.fname AS setter_fname,setter.lname AS setter_lname,
resetter.employee_id AS resetter_employee_id, resetter.fname AS resetter_fname, resetter.lname AS resetter_lname,
salesrep.employee_id AS salesrep_employee_id, salesrep.fname AS salesrep_fname, salesrep.lname AS salesrep_lname,
salesrep2.employee_id AS salesrep2_employee_id, salesrep2.fname AS salesrep2_fname, salesrep2.lname AS salesrep2_lname
FROM
core_records_appointments as appointments
INNER JOIN core_records_main as customer ON appointments.customer = customer.id
LEFT JOIN core_employees_main as originator ON appointments.originator = originator.id
LEFT JOIN core_employees_main as setter ON appointments.setter = setter.id
LEFT JOIN core_employees_main as resetter ON appointments.resetter = resetter.id
LEFT JOIN core_employees_main as salesrep ON appointments.sales_representative = salesrep.id
LEFT JOIN core_employees_main as salesrep2 ON appointments.sales_representative2 = salesrep2.id
 ";

L'operazione richiede alcuni secondi ma alla fine viene caricata.L'ultimo join che ho inserito sembra però interrompere la query insieme:

LEFT JOIN core_records_sales as sales ON appointments.day = sales.day_sold AND appointments.customer = sales.customer

Dopodiché ho un limite impostato e un gruppo per

Posso fare qualcosa per migliorarlo?Lo sto usando con jqgrid, non sono sicuro che sia d'aiuto

Answer 1

Come primo approccio, prova ad eseguire la query sul database utilizzando la sintassi EXPLAIN.Questo ti fornirà un'analisi della dichiarazione e ti dirà se utilizza degli indici.Se non utilizza indici o non ne ha abbastanza, prova ad aggiungerli alle tabelle.

Answer 2

Hai provato a fornire l'indice su tutte le colonne su cui ti stai iscrivendo?

PROVA a dare l'indice a tutti questi se non sono già dichiarati come indice