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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a86d71ba9ef7c3f0ea92ddc1eba3e7943ea3cb00b35d79a72ebcd174b1ce987' 
  AND token = 'mN/LA4eHKpz2pycUJemjtOUpk8ZMEP7QsWAY9J5Kqrs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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