SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f46c9af0837ff717c0069e76558491a738044829ee1b6938f28e1a72eec3f703' 
  AND token = 'o4x27PZ1A+OPh7P6pNE3Fv752oyucNFqxgxdnNJC6j0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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