SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46714392ff5bf85478dc6a299869fe86e2965b6d23a989df850ea4e5a9fa7296' 
  AND token = 'NKNaNzJGV0TG7v4gXG+9uCxPHvSi9CCEy8Ok44EPvDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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