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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4404e24a640fb7d67e2b638dcb8a4f6303c096d5ddf5b7e14e2da1fc300d682' 
  AND token = 'xmUM3e/mdXVufFoLTYUb3/onJiuZYNTCeB/DSOvTQgI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}