SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4fdfc04b9cf6dbc640cea2cf1900fb1e734a2fa870715f2e869eefadbea86c39' 
  AND token = 'GbtsS1Hr5MnFo3F41ea3UNkKiU0nx5qJWqUx97c13IM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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