Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5471d2ecfdf1c8fa70cf6811baca09e2c18a21241611a4d288635b4e02352a1' 
  AND token = 'jpE5B1NxxRNXzGoWxcbQuIRRA9PGP4gSOrGl6Mbnc9A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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