You can enable caching for virtual data sources
and tables that they store on the Cache Settings page
of virtual data source properties window.
About this task
When you enabled caching for a virtual data source, records
from the tables stored in this virtual data source are cached. If
you open one of these tables, its records will be retrieved from cache
rather than from the data source. You can also enable caching for
individual tables within a virtual data source.
To enable caching for virtual data sources:
Procedure
- Select to open the Create New Expiration Schedule wizard.
- From the Data source list, select
the data source to which you want to specify the cache expiration
scheduler.
- In the Schedule name field, enter
the name you want to use for this schedule.
- In the Data Expires area, specify
the period of the cache expiration. The available options are:
- Hourly: Select this option to
specify that the same cache data will be used for one hour period.
- Daily: Select this option to
specify that the same cache data will be used for a 24 hour period.
- Weekly: Select this option to
specify that the same cache data will be used for a period of 7 days.
- Monthly: Select this option to
specify that the same cache data will be used for a month.
- At specific date: Select this
option to specify that the same cache data will be used until a specific
date is reached. If you select this option, the cache will be updated
on the specific date.
- Never expires: Select this option
to specify that the same cache data will always be used. If you select
this option, the cache will never be updated.
- Always expired: Select this option
to specify that the data will always be updated every time a query
is run against this data source.
- If you selected Hourly, Daily, Weekly, Monthly,
or At specific date, click Next.
- Depending on the type of schedule that you are creating
one of the following variations of the Set schedule properties page
of the wizard opens:
- If you selected Hourly, specify
the date and time that the hour period will start in the Begin
date and the Begin time fields.
In the Expiration Interval area, specify expiration
interval in Hours and Minutes fields.
- If you selected Daily, specify
the date and time that the 24 hour period will start in the Begin
date and the Begin time fields.
You specify when the 24 hour period will occur in the Data
Expires area:
- Select Daily to specify that the 24 period
will occur every day.
- Select Each to specify that the 24 hour
period will occur every number of days and select the number from
the list.
- Select Days of week to specify that the
24 hour period will occur on one or more specific days. You must select
the check boxes for the proper days.
- If you selected Weekly, specify
the date and time that the week will start in the Begin
date and the Begin time fields.
You can select a number from the Each week list
to specify that the 7 day period will occur every number of weeks.
In the Days of Week area, specify particular
days on which the cache will be updated.
- If you selected Monthly, specify
the date and time that the month will start in the Begin
date and the Begin time fields.
You can enter a specific day in the Day field
or to specify that data retrieval will occur on a specific day of
the week in the month in the Or field. In the Select
Months area, specify the required months.
- If you selected At specific date,
specify the date and time that will trigger data retrieval in the Date
and time list. Click the cell, the ellipsis (…) appears.
Then click the ellipsis (…) to open a calendar where you will
select the date and time.
- Click Finish. The schedule is created
and listed in the Schedules node of the particular
virtual data source in the Repository Explorer view.