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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '76398c8f3fbb386d940a96ec8e9f5fc72874968e868601fe51bc4c9eba0a886a' 
  AND token = 'PYl/xFAwjTvSERHeHXysFaI9cImbRs3qzGC04/XjB8k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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