SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0b842d04b6e31e41d0615e3231adc03694c4427bddaf6b35a2013b14addf13c2' 
  AND token = '0161uTxyt03Ofn0AcnEPU6BxOLdr5eB15bgBZFQ1xjM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}