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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec6dc7bd8ed54826935075e84cd4f6cf7368063de220b93bd2cecf243d89a635' 
  AND token = 'SYHbmCfSPtBBZIUR1Vj2RJUm6cd4V2ywjVJBmvQuEKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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