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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5dbb5564027564e1fe24c0d8dc6d66603b9f2ad33f1e9c4ac3e1530f68c7b3c' 
  AND token = 'kq+9NNZfFIjfAIUMgcU81ysr98wj2na7WuG2m4QDN2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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