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InfinityOLEDBProvider – Receiving OPC HDA and HAE data using SQL queries

InfinityOLEDBProvider – Receiving OPC HDA and HAE data using SQL queries

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Purpose

Receiving data from sources that support OPC HDA and HAE interfaces by executing queries in SQL.

Features

  • Support for the select statement with some limitations.
  • Support for the first/last construct.
  • The data for each source is represented as a set of tables.
  • Two methods of selecting data from a table: using SQL-query and direct selection.
  • Ability to specify optimization conditions for the sample.

General Information

The InfinityOLEDBProvider component is designed to obtain data from sources that support OPC HDA and HAE interfaces by executing queries in the SQL language. The component is an in-process COM server that implements interfaces defined by the Microsoft OLE DB specification. In the client application, when connecting to the InfinityOLEDBProvider, the OPC HDA and HAE data sources for the connection are specified. For each data source, you specify an alias that is used when accessing source tables in SQL queries. When executing SQL queries, the select statement and the first/last construct are supported. The received data from each source is represented as a set of tables consisting of statistical and dynamic columns. You can obtain data from the server by direct selection (importing all data from the table) or by using the SQL query (importing data that satisfies the query).

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In order to reduce the time and resources spent on busting records in the form of OPC HDA and HAE source tables, it is recommended to optimize the selection of historical records. There are the conditions allowing to avoid search of records which should get as a result of request. When accessing the HAE source, the time filter allows to select records according to timestamp, and a free filter allows you to filter out those that do not satisfy certain additional conditions. When accessing the HDA source, the use of filters by tag and by time indicates by which tags and by which timestamps to select records, and the free filter allows you to filter out those that do not meet certain additional conditions.