Deprecated - Database compatibility

Everytime i install a new module i get this:

Fatal error: Allowed memory size of 16777216 bytes exhausted (tried to allocate 185966 bytes) in /webroot/vhosts/xxx/docs/drupal/includes/database.inc on line 159

Warning: Table 'watchdog' was not locked with LOCK TABLES query: INSERT INTO watchdog (uid, type, message, severity, link, location, referer, hostname, timestamp) VALUES (1, 'php', 'Table 'sessions' was not locked with LOCK TABLES\nquery: SELECT sid FROM sessions WHERE sid = '2ea56ecd358c1ef728d1a1c64041c63e' in /webroot/vhosts/paradise-bodies.com/docs/drupal/includes/database.mysqli.inc on line 151.', 2, '', 'http://www.paradise-bodies.com/drupal/admin/build/modules/list/confirm', 'http://www.xxx.com/drupal/admin/build/modules', '87.167.115.207', 1202714659) in /webroot/vhosts/paradise-bodies.com/docs/drupal/includes/database.mysqli.inc on line 151

I am trying to execute a query with 5 parameters, but it don't add more than 4 parameters. Is there a limit? I tried putting them inside an array, but the problem continues:

I need to upgrade my web server from mysql version 3.23.58 to version 4.0x in order to install another piece of software. Can I expect any problems with Drupal once I make this upgrade? I use a VPS and am nervous to ask my provider to make this upgrade because I do not want it to take my entire drupal site down. But, I also need to install the new software. Any resources you can point me to would be appreciated.

I want to take out a user's points from the points field in userpoints table,because i will use it to judge
a inputted number whether is bigger than this user's points,if bigger,drupal will tell you error.but the number taken out from the DB is always incorrect .the following code is my validate function:
function answers_validate(&$node)
{
global $user;
$points_user=$node->favorite_points;
$auid=$user->uid;
if($auid)
{
$totalPoints=(int)db_query('SELECT points FROM {userpoints} WHERE uid=%d',$auid);

Hi,

after stumbling upon the Gladius DB project, which seems to me to hypothetically work with Drupal instead of a MySQL database, i was wondering whether you could point me in the right direction as to where to start.

Description from sourcforge.net:

The most efficient flatfile database engine written in pure PHP, it is compatible with a subset of intermediate SQL92 and does not need any additional library! It perfectly understands SQL (also MySQL variant) and is also supported through ADOdb Lite.

And a description of a possible implementation:

Gladius DB engine can be used as stand-alone (including gladius.php) or with ADODB lite ( http://adodblite.sourceforge.net/index.php ) using the supplied driver gladius_driver.inc. If your databases' folder is not the gladius.php's folder, set the variable $GLADIUS_DB_ROOT before including gladius.php or calling ADODB's AdoNewConnection(). Example:

  global $GLADIUS_DB_ROOT;
  $GLADIUS_DB_ROOT = '/home/usr/databases/';
  
  include 'gladius.php';
  
  $G = new Gladius();
  
  $G->SelectDB('database_name/') or die;
  
  $G->Query('CREATE TABLE hypsin ( base FLOAT, root FLOAT)');

After listening to the MySQL webinar presented by Jeremy T. of tag1consulting.com I understood that he recommended InnoDB (and I personally would use InnoDB over non-ACID compliant ISAM too, regardless of any performance issues). I loaded drupal 6 2rc and it is still (seemingly) using ISAM. Would you recommend converting to InnoDB? Is Drupal 6 going to 'officially' switch over to InnoDB?
thanks, all
Lesley