SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84e79282dfc413485e7edd624530ad1b613d8e886ef5126f19318330f6b269d2' 
  AND token = 'k1/IKPjPqV+N1P3nLSP4pAR22F+H5KX6VpyFqi6ICFo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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