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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'dbc7427bdc036dacf5a8aeb0ab8ebdd22427e118155f1151a32f75e994ef82c9' 
  AND token = 'FE5u8MXEsMX+rLZebGemKf6xL+R8VPZceZ8X7jQ5cEw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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