dbExpress Components
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dbExpress is a set of lightweight database components that provide fast access to SQL database servers. For each supported database, dbExpress provides a driver framework that adapts the server-specific software to a set of uniform dbExpress interfaces. When you deploy a database application that uses dbExpress, you include a DLL (the server-specific driver) with the application files you build.
dbExpress lets you access databases using unidirectional datasets. Unidirectional datasets are designed for quick lightweight access to database information, with minimal overhead. Like other datasets, they can send an SQL command to the database server, and if the command returns a set of records, retrieve those records. Unidirectional datasets do not buffer data in memory, which makes them faster and less resource-intensive than other types of dataset. However, because there are no buffered records, unidirectional datasets are also less flexible than other datasets.
dbExpress connections, tables, views, and stored procedures that show up in a data tree view support drag & drop with native and managed vcl forms.
The dbExpress category of the Tool Palette contains components that use dbExpress to access database information. They are:
| Components | Function |
|---|---|
|
TSQLConnection |
Encapsulates a dbExpress connection to a database server |
|
TSQLDataSet |
Represents any data available through dbExpress, or sends commands to a database accessed through dbExpress |
|
TSQLQuery |
A query-type dataset that encapsulates an SQL statement and enables applications to access the resulting records, if any |
|
TSQLTable |
A table-type dataset that represents all of the rows and columns of a single database table |
|
TSQLStoredProc |
A stored procedure-type dataset that executes a stored procedure defined on a database server |
|
TSQLMonitor |
Intercepts messages that pass between an SQL connection component and a database server and saves them in a string list |
|
TSimpleDataSet |
A client dataset that uses an internal TSQLDataSet and TDataSetProvider for fetching data and applying updates |