Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da8e03635835c9e79661e3e42dce34143d171d4b5e024146a710b7ff434cb478' 
  AND token = '3+ehuB0zf+X6uBd6cJ38MMDn/Wau325ziKnL3Tbk9u8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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