SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '157e0487877ca61d2a2dbdd245a3fea16eba7cdd6d0b773616c05f0822a11178' 
  AND token = 'cCs6b5In50ASZL3H22zdH+QG/7bvq1L+MJrZHBI8mPo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}