SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e88559c0c6bb8422bac5345e2ac9896f8037d0b577ed0f01c38d4480c2ecc6d' 
  AND token = '1RXITPwtFG1JgD2mQp1hV3p74I9X1FKEYUF6+rjjJ6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}