Options - Database Explorer

These options govern how AQT obtains the information on tables (and other objects) in your system. If AQT is unable to correctly display the tables in your system you could try changing some of these parameters, otherwise they should not be changed.

Get Table Info from

This determines whether table information is obtained from the System Tables or from the ODBC API calls. The default is System Tables (if that option is available for this database).

This parameter cannot be changed while you are currently signed onto a database.

For a further discussion on this see System-Table Query Feature.

Show Favorites on Startup

If this option is selected, AQT will show the Favorites display when it opens the Database Explorer window.

If the database does not have any favorites defined, AQT will show the Objects display.

For DB2 for iSeries, support the *SYS Naming Convention

For DB2 for iSeries, table names can be referenced using schema/table-name, rather than schema.table_name. Example:

select * from QSYS2/SYSTABLES

This is known as the *SYS Naming Convention. You may wish to adopt this standard if you are running scripts that refer to tables using this convention.

If so, you need to:

• when you configure your ODBC Datasource, on the Server tab specify a Naming Convention of System naming convention (*SYS). This option is only available when using Client Access Express, and not if you are using DB2/Connect.
• on AQT Options, set the option For DB2 for iSeries, support the *SYS Naming Convention option

Number of items in History Cache

This specifies the number of entries in the object-list cache in the Database Explorer. Specify 0 to disable this feature. This value applies to each Database Explorer window, as each Database Explorer window has it's own cache.

The cache is held in memory; the larger this value, the more memory will be used by AQT. You should avoid specifying an unnecessarily high value.

If this value is changed, it won't come into effect until the next time you connect to a database.

History Cache will not be used if Disk Cache is enabled.

Get Related Table information from User Defined Relationships only

When using the Query Builder or the Link to Related Table feature of AQT, AQT needs to find information on table relationships. It get this from two places:

• from the database (eg. foreign key relationships)
• from User Defined Relationships

If you do not have any relationships defined to the database, the database query is superfluous and adds unnecessary overhead to AQT. In this case, you may wish to select this option. When this is done, AQT will not query the database for foreign key relationships - it will get related table information from UDRs only.

Only show filtered objects when invoke a sub-window

This option relates to a problem which occurs when you have a large number of objects in the object-list, plus a filter applied so that only a small number of these rows are displayed.

In this circumstances, AQT can be very slow to load the Generate DDL window, the Add Multiple Objects to Favorites window, and (in some cases) the Manage Multiple Objects (such as Drop Table) The slow time is because AQT is loading all the objects into the grid on these windows, then reapplying the filter.

If you are experiencing this problem, you should select this option. In this case, AQT will only load into these windows the objects which are displayed in the object-list. These windows will load much faster. The drawback is that the filter-box on these windows will be disabled; if you wish to have a different filter you will need to return to the Database Explorer window, change the filter, then reinvoke the sub-window.

For Oracle, use DBA dictionary views

This option determines which set of Oracle dictionary views AQT is to use to display the information in the Database Explorer. This takes values:

• No. AQT will use the ALL views
• Yes. AQT will use the DBA views
• Auto. AQT will run a query to determine whether you have access to the DBA views. If so, AQT will use the DBA views, if not, the ALL views

This option comes into effect immediately so can be changed during the course of an AQT session, though you may have to Refresh the middle grid and/or the Object Tree if they contain cached information.

There is more on this at Notes on Database Explorer for Oracle

Remember schema filters between sessions

When this option is selected, AQT will remember the schema filters between AQT sessions.

Disk Cache

When the Disk Cache is enabled, AQT will cache the Database Explorer displays to disk. This is similar to the History Cache (see above), however has a number of advantages:

• History Cache stores the data in memory, resulting in more memory usage. By contrast Disk Cache stores the data on disk.
• History Cache will lose the cache when AQT is closed. Disk Cache will retain the cached data between AQT sessions.
• With Disk Cache you can select whether you want this feature enabled for Schema lists, Objects lists or both.

If your system has a large number of database objects, enabling Disk Cache will result in a faster startup once you connect to a database.

Specify the following options:

• Use Disk Cache for Schemas - when this is selected, AQT will use the Disk Cache for the list of schemas. These are used when you click on an object-type in the Object Tree on the left panel.
• Use Disk Cache for Objects- when this is selected, AQT will use the Disk Cache for the list of objects. These are displayed in the Object List in the middle panel.
• Max cache files per database. This specifies how many files are to be held in the Disk Cache. This applies separately to Schema and Object caches - for instance if you have a value if 10, AQT will hold 10 schema cache files and 10 object cache files.

The directory cache files are held in is given in Options > File Locations