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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '6fc6bd363ca15c4e6d8c5848b9b1b85ec7a6b4668cb5ff3478bbf9f05b673612' 
  AND token = 'vJ/uDl32VpTJCdNei2YNG9EqA5vMnwmVD1HGD7iehd0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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