SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4d85ea07e9e74ac62c709ecce64531890bccc635e063e83b4f9b0ca85e754dc' 
  AND token = 'DvVRKMEDuHAACLIHBMBPNgSMMEwZG2gsyZ3jJHTFtaM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}