SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '858a9856b36ad1c833e92c6f66fbfc24066f446dc0773960fe8c11f8df675a52' 
  AND token = 'GPveMNU80Ul0vwtgdzceuIhi/VmlmLjZByBMbSEQ5AA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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