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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff872871a8af1cf882ee7d06f6f3c5015da2cbf5b00dcb50d2a379cff837489c' 
  AND token = 'vMHDXIVbP2Ve+0XFDFOtXwZQi5ciMVYTaRTlfnJ5/Lk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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