SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '29aba3b37d68a28250e5b99809d5136eec2ad100bba4bc496c70caba97762094' 
  AND token = 'iud1Scc+nbT2K0dGtH96X7OXX7Eb727eS1YkmQFsRAg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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