UniDAC

Using Advantage data access provider with UniDAC in Delphi

This article provides a brief overview of the Advantage data access provider for UniDAC used to establish a connection to Advantage from Delphi and Lazarus. You will find the description of some useful features and how to get started quickly.

Overview

Advantage provider is based on the ODBC provider. It uses Advantage ODBC driver to work with database. Main features of Advantage data access provider are:

The full list of Advantage provider features can be found at the UniDAC features page.

Both Professional and Standard Editions of UniDAC include the Advantage provider. Express Edition of UniDAC does not include the Advantage provider.

Compatibility

To learn the supported versions of Advantage Database Server, refer to the Compatibility section.

Requirements

Applications that use the Advantage provider require the following components to be installed on the client computer:

Deployment

To deploy Win32 applications built with run-time packages, it is required to deploy the adsproviderXX.bpl and odbcproviderXX.bpl files.

For more information about deployment of UniDAC-based applications, please, refer to the common Deployment topic.

Advantage-specific options

TUniConnection

Option name Description
DefaultType Specifies the type of database files to be used.

Supported values:

dtAdvantage (default)
Specifies that proprietary ADT tables with ADI index and ADM memo file formats will be used.

dtFoxPro
Specifies that FoxPro-compatible DBF tables with CDX index and FPT memo file formats will be used.

dtVisualFoxPro
Specifies that Visual FoxPro-compatible DBF tables with CDX index and FPT memo file formats will be used.

dtClipper
Specifies that CA-Clipper-compatible DBF tables with NTX index and DBT memo fields will be used.
ColumnWiseBinding

If set to True, the option enables Column-Wise Binding mode. The fefault value is False.

Note: Row-Wise Binding mode is enabled by default. However, some ODBC drivers don't support this mode. In such case, set the ColumnWiseBinding option to True.

ConnectionTimeout The time to wait for a connection to open before raising an exception.
ServerTypes Specifies the Advantage server types, to which connections should be attempted. Valid values include ADS, ALS, and AIS.
ADL - Remote , ALS - local, and AIS - Internet Servers.
These values can be logically OR'ed together with the "," in order to choose multiple server types. If multiple types are specified and multiple server types are available, the order of precedence is ADS first, AIS second, and ALS last.
UseUnicode Enables or disables Unicode support. Affects character data fetched from the server. When set to True, all character data is stored as WideStrings, and TStringField is replaced by TWideStringFiled.

TUniSQL

Option name Description
CommandTimeout The time to wait for a statement to be executed.

TUniQuery, TUniTable, TUniStoredProc

Option name Description
CommandTimeout The time to wait for a statement to be executed.
ExtendedFieldsInfo If True, an additional query is performed to get information about returned fields and tables they belong to. The default value is True.
FetchAll If True, all records of a query are requested from database server when the dataset is being opened.
If False, records are retrieved when a data-aware component or a program requests it. The default value is False.

TUniScript

The TUniDump component has no Advantage-specific options.

TUniLoader

The TUniLoader component has no Advantage-specific options.

TUniDump

The TUniDump component has no Advantage-specific options.

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