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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b6447b00adda8ca50e33d958fce3aa4c34b7e4cc3b5ec85b2f9312b9cc65a018' 
  AND token = 'vX9Za+Wo64rCtvs3dPcGD+OIjykXkoX+J8Gdt1uUB7U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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