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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'e546e89abe447081c7f2f0b38024384805eddf1e5cee97495d70fb9713019a4c' 
  AND token = 'GenUTBFirR04VZ6Rr49txs8Ui1+CnVDaRbSLz6V2Gk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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