# MySQL’s EXPLAIN PLAN

- ## To generate a plan:

  EXPLAIN SELECT tt.TicketNumber, tt.TimeIn,
  tt.ProjectReference, tt.EstimatedShipDate,
  tt.ActualShipDate, tt.ClientID,
  tt.ServiceCodes, tt.RepetitiveID,
  tt.CurrentProcess, tt.CurrentDPPerson,
  tt.RecordVolume, tt.DPPrinted, et.COUNTRY,
  et_1.COUNTRY, do.CUSTNAME
  FROM tt, et, et AS et_1, do
  WHERE tt.SubmitTime IS NULL
  AND tt.ActualPC = et.EMPLOYID
  AND tt.AssignedPC = et_1.EMPLOYID
  AND tt.ClientID = do.CUSTNMBR;

- ## The plan is described as results like this:

  TABLE TYPE POSSIBLE_KEYS KEY KEY_LEN REF ROWS EXTRA
  et ALL PRIMARY NULL NULL NULL 74
  tt ref AssignedPC,ClientID,ActualPC ActualPC 15 et.EMPLOYID 52 where used
  et_1 eq_ref PRIMARY PRIMARY 15 tt.AssignedPC 1
  do eq_ref PRIMARY PRIMARY 15 tt.ClientID 1

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