Please can someone help me optmize this query, it is slow and brings the same data for the debtage column
SELECT customer.custid,customer.compname,customer.phone,customer.depot,acctofficer.acctfullname AS acctoff, STR_TO_DATE(mastorders.lastsuppdate,'%d-%m-%Y') AS purchdate, STR_TO_DATE(transactions.timestamp,'%Y-%m-%d') AS debtage, format( customer.balance, 2) AS balance, customer.balance AS balance1 FROM customer,mastorders,acctofficer,transactions WHERE customer.custid=mastorders.custid and acctofficer.acctoffid=customer.acctoff AND customer.depot='$depot' GROUP by customer.id ASC.
Thanks for your help.