SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c5888fcdca809e9e77dba14decb3529a74fa63bd0c3f76916a2b974a5eae40a7' 
  AND token = '5GCYcvr1QuF/Ap3lR8THypDcMCIVAjTNg1TWBUoHWzc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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