SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14847f616231d6268bf49b432760e8fba030119f4e58998c30922161481bad50' 
  AND token = 'mAIv9qzEqt8bTDKvVQPjTv3ZNp4vz0Tw6bBhXCMvYmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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