SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '98f71df4a125854ec0eb17b66c4ffd4f8843300773ebddf9d4ce1d061aca5666' 
  AND token = 'HhIvrZLYjak5hOu5Qud4ouO4B8RFZF2G/EyVixl7GCc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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