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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d78c497951bc945bbd765b7a6a70fc4531f7a7f2df5d6abfedebdeaf29a2ed4' 
  AND token = '4TP0LJJZdIHUMjXAEze3Dev0saYwYmVfM5Q+ojDk8fI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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