SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7b49bd86031ec4405a5473f16055dab9de0fd3c5424393a282ee95962b8439e' 
  AND token = 'Qkgq0BIPVRRbY/jntc8CKO8eHztsNsJoog07eecXlB4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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