SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4529818a7a0d009048653bb7f25c425e197db57ed11c79bfbb87eee605504d04' 
  AND token = 'Q2Vrl8igsxzpByfXj++vX30O/++gJiXXAuPb4BF/LM4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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