Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c897be91f1045a76cf7f50fbd48aeaa967b8fee6b2e4002dc40e74da9d8ea4c6' 
  AND token = '5GIRJt9dwNiAsiNZFxdBGTM32AR/3BchD7AFY35nOYc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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