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ADO - page of object PmaAdo

Description:
Basic settings for database access via the ADO technology.
Configuration items:
Database connection parametersDatabase connection parameters by the DbOpen method in the form of ADO ConnectionString. The ADO ConnectionString (http://www.connectionstrings.com) contains all necessary parameters needed by the ADO Connection object for database connection via the selected ADO Provider. The typical parameters are represented for example by connection provider (provider), server address (server), database name (database), login name and password (uid, pwd), etc. The parameter list and exact syntax is defined by the corresponding ADO Provider, parameters may differ by individual ADO Providers. However for the sake of compatibility most providers ADO Provider understand multiple names of the main parameters simultaneously (e.g. the database name can be represented by database, data source, dbq, etc.). Caution: The syntax of this string is different than other strings used in the PROMOTIC system, the value and the name are separated by =, not by "colon" (:). Entries with assigned value are separated by a semicolon, for example "provider=SQLOLEDB;server=.\SQLEXPRESS;database=pm_data;uid=pm_admin;pwd=pmadmin;".

This configurator sets the initial value of the property DbConnectionString.

Macro expression can be used for input (it is evaluated after starting the application).

Values can be edited manually, or created by the button on the right, that will open the window for Window of recommended settings of the connection string.

The defined parameters may not always be valid (for most common cases), it depends on the selected ADO Provider.

"provider:xxx;" (optional) - Specifies which ADO Provider will be used for database connection. It can be the Microsoft company ADO Provider, or another ADO Provider can be used, e.g. "provider=MSDASQL;"
MSDASQL (default) - Microsoft provider for ODBC.
SQLOLEDB - Microsoft provider for MS SQL Server.
Microsoft.Jet.OLEDB.4.0 - Microsoft provider for Access (*.MDB).
"server=xxx;" (optional) - SQL server name, that holds the database to connect to. Depends on the SQL server type. The name usually consists of the computer name (IP address) and server instance name, separated by separator character, for example "server=.\SQLEXPRESS;".
"database=xxx;" (optional) - Database name, e.g. "database=pm_data;".
"dsn=xxx;" (optional) - Name of registered ODBC DSN source. In this case, there is no need to enter the server, database or driver, because all thise information is defined in the registered DSN source, for example dsn=pm_data;.
"driver=xxx;" (optional) - Name of ODBC driver, e.g. driver={Microsoft dBASE Driver (*.dbf)};.
"uid=xxx;" (optional) - User name to be used for database connection, e.g. uid=pm_admin;.
"pwd=xxx;" (optional) - User password, e.g. pwd=pmadmin;.
Additional parameters of database connectionAdditional parameters of database connection by the DbOpen method represented by string. Entries are in KeyVal format, for example "connect:async;connectiontimeout:30;commandtimeout:60;".

This configurator sets the initial value of the property DbConnectionParams.

Macro expression can be used for input (it is evaluated after starting the application).

"connect:xxx;" (optional) - Specifies the connection type. The default is synchronous connection, i.e. the method will execute the connection and wait for operation result.
async - Asynchronous connection, i.e. the method will create the connection request and does not wait for result. Corresponds to the ADO adAsyncConnect value.

Caution: Asynchronous programming frequently causes comlications, therefore it is recommended to use the synchronous attitude. If there is a chance, that the synchronous requests may take too much time and there is a possibility of timeout, then it is recommended to execute all operations in the working thread (See PmaSequencer").

"connectiontimeout:xxx;" (optional) - Specifies the number of seconds to wait before the connection is opened (default is 15 seconds).
"commandtimeout:xxx;" (optional) - Specifies the number of seconds to wait before the command is executed (default is 30 seconds).
Connect to the database on application launchIf checked, then the PmaAdo object will connect to the database automatically on application launch.

History:
Pm9.00.02: New options "connectiontimeout:xxx;" and "commandtimeout:xxx;" in the "Additional parameters of database connection" configurator that can be used to define the waiting time before connection or command execution.
Pm8.01.00: Created
PROMOTIC 9.0.5 SCADA system documentation - MICROSYS, spol. s r.o.

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