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#Db optimizer xe3 code
#Db optimizer xe3 windows

Type you're using to get the data from the server. You didn't mentioned which server back-end you are using, nor what Delphi dataset

#Db optimizer xe3 code

(This isn't exactly an answer to your q, but it may provide some usual information and I've included some code which may help inform your implementation).

If you try to get the number of records, and don't do it in a separate SELECT COUNT query or if the db library doesn't return it somehow, the TDataset component may fetch all rows just to get the count.

For example, Developer Express grids usually load the whole dataset to enable features like sorting, filtering and grouping locally, unless you set them to not do it.

Some controls may load the whole dataset anyway.

The query could run slower, and more server resources are used.

If you don't limit the result set at the SQL level, the database may still need to generate the whole result set.

#Db optimizer xe3 windows

In a native Windows application, you usually don't need the "paging" metaphor web UI uses, because it is far easier to use some control that can scroll up and down while caching data in local memory or disk. It requires a little more code to work, though. It can load data incrementally, and it will cache already fetched rows. The TClientDataset + Provider combo offers a similar functionality, independent from the database. Some can also cache query results, and avoid to re-execute a query if possible. Some databases will be able to return you only a given number of records until you ask for more, if the Delphi data access library you use also supports that feature and can set it. There are different ways in Delphi to limit the number of records loaded by a query - it also depends on what database you're using and what data access components. Is there such a component or configuration exist for Delphi XE? I just need a nudge toward the right direction. SELECT * FROM tbl_product_master LIMIT 0,20 īut because the database component knows I have already call this query before, and it already saves the result in the cache, it immediately returns the result from the cache, not firing the query again to the database, thus resulting in faster program.

The program attempts to load the first 20 lines again. SELECT * FROM tbl_product_master LIMIT 21,40

The program loads the next 20 lines for page 2 from database using query. SELECT * FROM tbl_product_master LIMIT 0,20 The program loads the first 20 lines for page 1 from database using query. I want to ask, is there any way for Delphi to cache a query call result, so that for the same query, the database component doesn't query again to the database, but return for the cache instead? I'm working on a Delphi XE-based desktop program with database, and I have noticed that it will be too big for the program to load an entire table before display it to user per page every time they want to browse for products, but it will be also inefficient for the program to load and reload each page as the user browse like in browser.