Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'ccb3aba60ac17440b37f7c097c5b693723724bee0d03bca2ff34cec427712ba2' 
  AND token = 'Dyxk/FZFnCj/rfzMIC3JZm2EZsuA1GsaLoAvFmU3FdU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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