SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '895c423fc96116502000dd3e9c251fd79bc0218139e183240d6e5513d16d86df' 
  AND token = 'ODGidS3FdHe/aSyMxnmy6hNEL5dSFXT9qqHRd/SJvWU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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