PGSQL errors with comment_user_uid (filter and argument)

Do you understand where the problem in the query is? I don't actually understand the error message.

What does "argument of OR" refer to?
Is it this? I notice the second OR is lowercase.... does postgres confuse this for an arg? I don't get it.

(node.status <> 0 OR node.uid = 1 or 1 = 1) 

I am fairly familiar with the views api, and can look through and play around with some of the views includes in the project_issue module.

This is my first drupal installation with pgsql, but I am in the process of learning to become a pgsql developer, so I am keen to work this out.

OK I'm on to something.

The original query that fails:

SELECT COUNT(*) FROM (
	SELECT node.nid AS nid 
	FROM node node 
	INNER JOIN project_issues project_issues ON node.nid = project_issues.nid 
	INNER JOIN users users_project_issues ON project_issues.assigned = users_project_issues.uid 
	LEFT JOIN node node_project_issues ON project_issues.rid = node_project_issues.nid 
	INNER JOIN node node_project_issues_1 ON project_issues.pid = node_project_issues_1.nid 
	INNER JOIN project_projects node_project_issues_1__project_projects ON node_project_issues_1.nid = node_project_issues_1__project_projects.nid 
	LEFT JOIN history history_user ON node.nid = history_user.nid AND history_user.uid = 1 
	LEFT JOIN project_release_nodes node_project_issues__project_release_nodes ON node_project_issues.nid = node_project_issues__project_release_nodes.nid 
	INNER JOIN node_comment_statistics node_comment_statistics ON node.nid = node_comment_statistics.nid 
	WHERE (node.status <> 0 OR node.uid = 1 OR 1 = 1) 
	AND (project_issues.sid in ('1', '2', '4')) 
	AND (node.uid = 1 OR (SELECT COUNT(*) FROM comments c WHERE c.uid = 1 AND c.nid = node.nid)) 
) count_alias

Here is a query that works:

SELECT COUNT(*) FROM (
	SELECT node.nid AS nid 
	FROM node node 
	INNER JOIN project_issues project_issues ON node.nid = project_issues.nid 
	INNER JOIN users users_project_issues ON project_issues.assigned = users_project_issues.uid 
	LEFT JOIN node node_project_issues ON project_issues.rid = node_project_issues.nid 
	INNER JOIN node node_project_issues_1 ON project_issues.pid = node_project_issues_1.nid 
	INNER JOIN project_projects node_project_issues_1__project_projects ON node_project_issues_1.nid = node_project_issues_1__project_projects.nid 
	LEFT JOIN history history_user ON node.nid = history_user.nid AND history_user.uid = 1 
	LEFT JOIN project_release_nodes node_project_issues__project_release_nodes ON node_project_issues.nid = node_project_issues__project_release_nodes.nid 
	INNER JOIN node_comment_statistics node_comment_statistics ON node.nid = node_comment_statistics.nid 
	WHERE (node.status <> 0 OR node.uid = 1 OR 1 = 1) 
	AND (project_issues.sid in ('1', '2', '4')) 
	AND (node.uid = 1 OR (SELECT COUNT(*) FROM comments c WHERE c.uid = 1 AND c.nid = node.nid) > 0) 
) count_alias

Pay attention to the 2nd last line. In the original query the syntax is "AND (x compared to y OR n)" whereas I've changed it to "AND (x compared to y OR n compared to m)" . I believe postgres expects each part of the WHERE to evaluate to a boolean TRUE or FALSE. Simply evaluating to a postive number does not equal TRUE.

I believe this is coming from /views/modules/comment/views_handler_filter_comment_user_uid.inc (and possibly similar) files.

<?php
    $this->query->add_where($this->options['group'], "$this->table_alias.uid " . $condition . " OR
      (SELECT COUNT(*) FROM {comments} c WHERE c.uid " . $condition . " AND c.nid = $this->table_alias.nid)",
      $args);
?>

I'll leave it to you whether to move this to the views project.

No I was wrong it's coming from an almost identical piece of code in /views/modules/comment/views_handler_argument_comment_user_uid.inc

I have not applied your patch, but looking at it, these are the exact changes I made to fix the problem earlier today. Even if the patch fails to apply for some reason the changes indicated in it are correct.
I can test it out tomorrow to confirm, and try the advanced search function.