SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e03c19168ea63d0b388981b35023403a2ed61d68b8595aa4b0023bc3df3d8503' 
  AND token = '469o9+Q31FQebvZLbkUccVS/Tjeg5z4M0xgIKi0ktB8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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