This commit takes care of the following issues/improvements.
* Adding missing imports for unauthorised in database module
* Node under Servers Nodes (i.e. Databases, tablespaces, roles nodes)
need to be inherited from PGChildNodeView (and, not from NodeView) for
adding server version check for their children.
* Adding statistics for database, and tablespaces in its node (not, yet
in UI)
* Renaming the camel case methods with proper name.
(i.e. getSQL -> get_sql, getNewSQL -> get_new_sql, etc.)
* Fixed the functions going beyond the text limit (column: 80) in
Databases, Roles & Tablespaces modules.
* Fixed the node method of Database module, which was not tested ever.
* We do not need separate SQL template for fetching the name (i.e.
get_name.sql), using the 'nodes.sql' for the same.
* Optimise the query for fetching ACLs for the database node, we didn't
require to join certain tables, while fetching only the ACLs.
* Introduced the list of the ACLs (regular and default ACLs for
different type) supported by each version [Databases Module].
* Renamed the templates 'get_nodes.sql' to' nodes.sql' to make it
consistent with other modules.
* Removed the checks for the authentication table use, as we don't need
to expose the password to the users (even the encrypted MD5). Using
the pg_roles view always for fetching roles/users information now.
* Resolved some typos in unreachable (specially the exceptions
catchment area.)
* Logging the exception in the application.
* Using qtLiteral, qtIdent properly in the templates (do not assume
about the types of data.)
* Using tsid as identifier instead of did for the tablespaces.
* Using nodes method of tablespace view for fetching individual node
information.
* Removing the hardcoded node information from the 'parse_priv_to_db'
function, and pass on allowed ACLs by the caller nodes.
* Using 'nodes.sql' to fetch name of the template instead of writing
that in the delete.sql template, which is definitely wrong place to
fetch the name of the object. [Tablespace Module]
We know that current implemenation have some limitations:
i.e.
* We should not show the template0 in the browser tree.
* Should not connect to the database which does not have permission to connect the server by the current user.
* Show default previlige for PUBLIC in creation mode.
* Allow to create/database database only if current user have sufficient permission.
* Do not show reversed engineered SQL in all supported version.
* Do not showing system database or not.
Author: Khushboo Vashi, Harshal Dhumal, Murtuza Zabuawala
Reviewed by: Neel Patel, Akshay Joshi
