SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2dc276f3f9538a5bc957a2db29eabf73c9f6bba3bfa329481aaab3b8c852b931' 
  AND token = 'Asg9VIlmL6QExCdveJrVxIjQZexj179EkX9QILCu220=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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