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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4b78e9e38048d2a641263ce400c0f1bba7fc52d42a678f0870807b3dea370e39' 
  AND token = 'RokF/yTZbZEawEih/4MymcHF5YneP8whHiWxMi242Rg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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