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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '90807eaddc438eec78bc3d1beb53a871e2be714b77575ebf36e7b80a0f30bcfe' 
  AND token = 'tEyqjzDBDB+ttj4F1ogFRiTeCKHMw2lb1HZ0bNPr8ew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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