SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '792b87ed60a9f98e111613af8704bc147e56494b493f4db34000003e1c8f6b65' 
  AND token = 'YGgRQzkVxXa4OJ54mChNV5OLnrl0a5+hacboSQA6V8Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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