Data Controller: Server Mode
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Server mode is a fast, efficient data loading mode specially designed to work with large datasets (those with more than 50,000 records). In this mode, the initial page will be displayed immediately, regardless of the number of records in the data source, and subsequent data will be loaded rapidly when scrolling. Loading records in small sets, and performing data-aware operations on the data server side are the key features of server mode that ensure fast access to data, even if the sorting, grouping, filtering, and summary features are used.
The current server mode implementation provides support for Microsoft SQL Server, Microsoft Access, MySQL, Firebird, InterBase (see the note below), Oracle, Advantage, PostgreSQL, and SQLite databases. The server mode requires special data source components, which utilize a connection object (a TCustomConnection descendant) to access and retrieve data for bound data-aware controls. Currently, only the ExpressQuantumGrid control provides support for server mode.
The server mode data source components that are shipped with the ExpressDataController include:
The FireDAC connection-based data sources (TdxServerModeFireDACDataSource and TdxServerModeFireDACQueryDataSource);
The dbExpress connection-based data sources (TdxServerModeDBXDataSource and TdxServerModeDBXQueryDataSource);
The ADO connection-based data sources (TdxServerModeADODataSource and TdxServerModeADOQueryDataSource).
In turn, these data source components can be grouped by their data retrieval method into the following categories:
Table-based data sources providing access to the entire database table or view (TdxServerModeFireDACDataSource, TdxServerModeDBXDataSource, and TdxServerModeADODataSource);
Query-based data sources providing access to the result set returned by a specified SQL statement (TdxServerModeFireDACQueryDataSource, TdxServerModeDBXQueryDataSource, and TdxServerModeADOQueryDataSource).
Important
Query-based server mode data sources do not support Inter