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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd21e2366f78767bda31b7a121713af7ad1e7ae3aaf0d26ae2c272b9e541baa77' 
  AND token = 'RHw9W752QnvVUrnQVVFJVw1M3xdK6dsWkZd1Rg+JAlM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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