SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dde721bac147cbc855ca63c795b365070ac3a3557d4b160bfdb8e1f97124d5d1' 
  AND token = 'Tf/4i17JCRQlBGCjIkzr6sCvasdOec4aoSOSmnu8kJI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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