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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c21fe0f5af964a491d1f59a8c9df7163dc032b5ac9776fae22cd1915e9f40e04' 
  AND token = 'jO5+CmXdNxcZAMEgb6mTAgMbziqqa5ZJSRzHyGCBdvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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