SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb5c66a779440d69a5cfefdc323a0165a9ddde583f9d5fca2bca3ef31b22d393' 
  AND token = 'NJaXmFDjYVcvIDsebyduGlMXUGz/hpqX9jkm3+QiA70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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