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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b6eafbc0b2be840d313f7df9a9605971acba947d29b447f5af39a57a9bb1d34a' 
  AND token = 'ZB1iLkj7dwX8uvIeUewkLtEYKKq8iUihtWEuH8G4M60=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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