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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f3e9a1460cc19a20833d55e73e0f7c3c14ca21a805dfc9e0df4b9656408bd57' 
  AND token = 'ekhx/yMr/ffTd8z160ZpdKQf3UbaTjJOMR7fZZkuRxA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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