SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e13e29617c5cdae9fa0fccfe870abc147792aa59311dd36782211ee614065ef' 
  AND token = '8BZA/Ex097+6hqB02g03ex0nOVhI5PIZ1B7TRji6rjI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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